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374 Cards in this Set
- Front
- Back
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an area on an enzyme that binds substrates in a chemical reaction
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active site
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a substrate attached to an enzyme's active site
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enzyme-substrate complex
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The body relies on ______ to speed metablic reactions up
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catalysts
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Althought enzymes increase the rate at which chemical reactions occur, they themselves _____ under go change
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do not
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Enzymes that catalyze hydroylisis reactions are called _________
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hydrolases
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enzymes that transfer atoms/ functional groups from one molecule to another are called ________
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transferases
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The shape of the active site changes to fit ________
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the substrate
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The active site wraps around the substrate, altering its ________ and transforming it into the product
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chemical structure
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What are examples of hydrolases which are essentian for digestion?
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lipase, amylase, protease ( pepsin , trypsin, chymotrypsin, and carboxypeptidase)
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catalyze reduction-oxidation reactions that involve the addition or removal of hydrogen ions and electrons to or from one compound to another
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oxidoreductases
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What are examples of redox enzymes?
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dehydrogenase, oxidase, reductase, and catalase
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_________ transfer an amino group from an amino acid to an alpha ketoacid
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transaminases
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transfer methyl groups
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thansmethylases
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transfer phosphate groups ( polymerase)
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kinases
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______ is essential for DNA and RNA synthesis
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polymerase
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hundreds of chemical reactions involved in the breakdown synthesis and tranformation of the energy yielding nutrients ( glucose amino acids and fatty acids) to meet the body's need for energy (ATP)
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energy metabolism
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chemical reactions that take place in the body
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metabolism
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chemical reactions that enable cells to store and use enrgy from nutrients
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energy metabolism
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a series of interrelated enzyme-catalyzed chemical reactions that take place in cells
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metabolic pathway
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a molecule that enters a chemical reactions
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substrate
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a molecule produced in a chemical reaction
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product
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a product formed before a metabolic pathway reaches completion often serving as a substrate in the next chemical reaction
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intermediate product
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The ____ of metabolic pathways can enter other metabolic pathways as substrates
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end product
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Metabolic pathways can be ____ or _____
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catabolic or anabolic
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____ release energy through the breakdown of complex molecules into simpler ones
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catabolic
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_____ require energy (ATP) to construct complex molecules from simpler ones
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anabolic
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The energy made avalible by catabolic reactions often drives ________
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anabolic reactions
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The breakdown of glycogen into glucose involves a series of ______ reactions
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catabolic
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The synthesis of glycogen from glucose involves a series of ______ reactions
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anabolic
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What are the metabolic fuels?
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glucose fatty acids and amino acids (alcohol can be used but not normal)
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After eating a meal these energy sources are excessively avalible, during this time anabolic pathways favor the storage of excess glucose fatty acids and amino acids as ____________
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glycogen, protein, triglycerides
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When blood glucose levels get lower, catabolic pathways increase fuel avaliblilty by breaking down the body's stored energy reserves _________ into glucose amino acids and fatty acids
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glycogen protein and triglycerides
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in this way, the body shifts from anabolic to catabolic pathways in response to ____________
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energy avaliblity and need
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series of metabolic reactions that breakdown complex molecules into simpler ones often releasing energy in the process
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catabolic pathways
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series of metabolic reactions that require energy to make complex molecules from simpler ones
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anabolic pathway
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In _______ carbohydrates protein and triglycerides are broken down to form glucose amino acids fatty acids and glycerol. Energy is released during these processes
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catabolic pathways
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In ______ glucose amino acids fatty acids glycerol are used to synthesize carbohydrates proteins and triglycerides. Energy is needed for this process
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anabolic pathways
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catalyze the addition or removeal of functional groups from substrates
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lyases
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_____ add or remove water to double bonds
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hydrases
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_____ remove carboxyl groups from compounds (eg, pyruvate decarboxylase)
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decarboxylase
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catalyze the rearrangement of atoms in a molecule without changing the molecular formula
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isomerases
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____ rearrage atoms in simple sugars and fatty acids ( eg, phosphohexose ? is essential for the conversion of glucose to fructose)
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isomerases
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catalyze the joining of two molecules to forma larger one using ATP as an evergy donor
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ligases or synthetases
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___ synthesize protein lipid polysaccharides and nucleic acids
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ligases
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What do enzymes do as biological catalyst?
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1. the substrate binds to the active site of the enzyme, forming an enzyme-substrate complex 2. the shape of the active site alters the chemical structure of the substrate tranforming it into the product 3. the product is released freeing the enzyme to bind another substrate
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enzymes are said to have ______ meaning that each enzyme interacts with only certain substrates
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specifity
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Because of enzyme ? the body makes thousands of different enzymes to catalyze thougsands of different reactions
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specifity
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a non protein, inorganic, component of an enzyme, often a mineral, needed for its activity
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cofactor
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organic molecule often derived from vitamins needed for enzymes to function
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coenzyme
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the oxidized form of the coenzyme that is able to accept 2 electrons and 2 hydrogen ion forming NADH + H+
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NAD+ ( nicotinamide adenine dinucleotide)
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the oxidized form of the coenzyme that is able to accept 2 electrons and 2 hydrogen ions forming FADH2
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FAD (flavin adenine dinucleotide)
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the oxidized form of the coenxyme that is able to accept 2 electrons and 2 hydrogen ions forming NADPH + H+
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NADP+ (nicotinamide adenine dinuecleotide phosphate)
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chemical reactions that take place simultaneously often involving the oxidation of one molecule and the reduction of another
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coupled reactions
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For the enzyme to function, the cofactors must be attactched to its _____
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active site
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NAD+, FAD, and NADP+ are examples of ???
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coenzymes
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____ are not actually part of the enzyme structure, they assist enzymes by accepting and donating hydrogen ions, electrons, and othe rmolecules during chemical reactions
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coenzymes
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_____ involve the gain and loss of electrons
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reduction-oxidation (redox) reactions
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These redox reactions that occur simoltaneously are offten reffered to as
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coupled reactions
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during ____ one molecule is being oxidized while another is being reduced
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coupled reactions
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____ allow energy to be transferred from one molecule to anothe rand require a type of enzyme called a dehydrogenase
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coupled redox reactions
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Coenzymes exist in two forms.... ___ and ____
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oxidized(NAD+, FAD, NADP+) and reduced(NADH +H+, FADH2, NADPH+ H+)
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When energy rich molecules are oxidized their electrons and hydrogen ions are transferred to ____ and ____
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NAD+ and FAD
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The coenzyme ___ can accept 2 electrons and 2 hydrogen ions forming _______
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NAD+ & NADH+H+ ; although 2 hydrogen ions are transferred to NAD+ only 1 attaches the second remains in the solution
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The energy carried by these reduced coenzymes (NADH+H+ and FADH2) is used to power the synthesis of the body's most important energy source _____
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ATP adenosine triphosphate
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The reduced form of the coenzyme NADH+H+ plays an important role in the energy requiring ____ pathways
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anabolic
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________ is needed for the synthesis of new compound int he body such as fatty acids cholesterol and five-carbon sugars required for DNA and RNA
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NADPH+H+
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NADPH+H+ is transformed into NADP+ when it ______
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releases 2 electrons and 2 hyrogen ions
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The pathway or combination of pathways used by the body depends primarily on ________.
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energy (ATP) avalibility
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a type of enzyme that catalyzes the removal and transfer of electrons and hydrogen atoms between organic compounds
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dehydrogenase
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The hormone ___ is released from the pancreas in reponse to elevated blood glucose and promotes energy storage.
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insulin
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The hormone ____ is released from the pancreas in repsonse to low blood glucose and promotes the breakdown of liver glycogen and the subsequent release of glucose into the blood
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glucagon
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_____ are important regulators of energy metabolism helping the body shift between anabolic and catabolic pathways
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hormones
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______ can detect changes in evergy avalibility and respond by secreting appropriate hormones
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endocrine tissues
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Hormones from the endocrine tissues then suppress or activate key enzymes in metabolic pathways to _____
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switch on and off metabolic pathways
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The primary hormones involved in the regulation of catabolic and anabolic pathways are ______________.
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insulin, glucagon, cortisol, and epinephrine
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___ is an anabolic hormone that promotes energy storage in the forms of glycogen triglyceride and protein
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insulin
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To promote energy storage insulin ________anabolic pathways and _______ catabolic pathways
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activates and inactivates
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When energy avalibilty is limited, the pancreatic hormone _____ promotes catabolic pathways and inhibits anabolic pathways
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glucagon
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By promoting catabolic pathways, glucagon increases energy avalibility by ________ energy yielding molecules that have been stored
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moblizing
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During times of stress and starvation, ________ hormones released from the adrenal glands also play important roles in directing neergy metabolism
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cortisol and epinephrine
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_____ and _____ sitmulate catabolic pathways that help increase fuel availability.
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cortisol and epinepherine
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____ sitmulate the breakdown of muscle glycogen to increase glucose availability.
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cortisol and epinepherine
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The energy stored in the chemical bonds of nutrients must be converted into a form that cells can use -- mainly ___
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ATP
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____ is a molecule uniquely suited to tranfer the energy contained in its hcemical bonds to chemical reacitons hta tto occur require energy
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ATP
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What does ATP provide energy for?
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protein synthesis, muscle contraction, active transport, nerve transmission, and all other energy requiring reactions tha ttake place in the body
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The energy contained within certain nutrients cannot be tansferred directly to ATP; that transfer requires intermediate steps that involve the coenzymes ? and ?
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NAD+/NADH+H+ and FAD/FADH2
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The ATP molecule consists of ____
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sugar ribose, base- adenine, and chain of 3 phosphate groups
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The _____ are high energy bonds that enable ATP to both store and release energy.
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the chemical bonds holding the phosphate groups together
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When the cells need energy , a _____ is broken off of ATP, releasing energy, and an inorganic ?
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phosphate group
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When a phosphate group is broken off ATP becomes ? which is used to drive metabolic reactions that require energy
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ADP
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The energy released from the breakding of ATP's phosephate bond is used to _____
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drive metabolic reactions that require energy
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ATP can be synthesized in two ways ... ___ and ___
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substrate phosphorylation and oxidative phosphorylation
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_____ occurs when a phosphate group is added directly to ADP; does not require oxygen and is therefore important when tissues have little oxygen available to them
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substrate phosphorylation
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Little ATP is synthesized through _____
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substrate phosphorylation
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the chemical reactons tha tlink the oxidation of NADH + H+ and FADH2 to the phosphorylation of APD to form ATP and water
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oxidative phosphoralyation
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oxidative phosphorylation accounts for approximately ___ of ATP production and involves a series of linked chemical reactions tha tmake up the electron trasnport chain
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90%
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located in the inner membrane of the mitochondria
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electron transport chain (system)
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The convuluted membrane divides the inside of the mitochondrion into innte ran dout compartments called _____ and ____
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mitochondrial matrix and intermembrane space
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inner compartment of the mitocondrion
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mitochondrial matrix
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the space situated between the inner and outer mitochonrial membranes is called ___
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intermembrane space
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____ consists of a series of protein complexes that are embedded in the inner mitochondrial membrane
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electron transport chain
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When NADH + H+ and FADH2 enter the electron transpot chain, enzymes remove their electrons and hydrogen ions regenerating NAD+ and FAD; the released electrons and hydrogen ions ______
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then take seperate routes
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The electrons released in electron transport chain are passed along the protein complexes which generates energy that is used to ______.
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pump hydrogen ions out of the mitochondrial matrix and into the intermembrane space
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The accumulation of hydrogen ions in the intermembrane space creates powerful force and when gained enough strength, the hydrogen ions re-enter the mitochondiral matric by passing through narrow channels. the movement through these channels releases energy that is used bo the enzyme _____ to attach a phosphate group to ADP, thus producing ATP
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ATP synthase
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NADH + H+ and FADH2 enter the electron transport chain at ?locations along the protein complexes, which is why the amount of ATP generated by these coenzymes differs.
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different
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Because NADH+H+ enters ? along the chain the ATP yeild is approximately 3 ATP and 2 ATP for NADH+H+ and FADH2
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higher
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ATP yield are often estimated on the basis of ___ ATP per NADH+H+ and __ ATP per FADH2
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3 and 2
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At the completion of the electron transport chain a group of iron containing protein complexes called ? reunite the electrons and hydrogen ion to form hydrogen which then form with oxygen to form water.
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cytochromes
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Because oxygen is essinetial for these reactions, the electron transport chain is considered a(an) ________ process
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aerobic metabolic process
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a series of chemical reactions that transfer electrons and hydrogen ions from NADH+H+ and FADH2 along protein complexes in the inner mitochondrial membreane, ultimately producing ATP
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electron transport chain
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a mictochondiral enzyme that adds a phosphate ot ADP to form ATP
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ATP synthase
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iron containing protein complexes that combine electrons hydrogen ions and oxygen to form water
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cytochromes
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What are hte stages of Catabolism: Breakdown of macronutrients?
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1. complex molecules broken down to building blocks 2. building blocks enter specific pathways and converted into intermediate products 3. intermedicate products enter citric acid cycle and broken down 4. NADH+H+ and FADH2 enter electron transport chain
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What is the 1st stage is Catabolism: the break down of macronutrients?
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breaks down complex molecules into the fundamental building blocks ( glycogen to glucose, protein to amino acids, and triglycerides to fatty acids and glycerol)The metabolic pathways that break them down are glycogenolysis, proteolysis, and lipolysis.
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What happens in stage 2 of Catabolism?
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the building blocks enter specific pathways where each is converted into an intermediate produc thtat can enter into the citric acid cycle
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What happens in stage 3 of catabolism?
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begins when intermediate products enter the citric acid cycle and are broken down further to form carbon dioxide releasing energy in the process. much of the energy released is transferred to the coenxymes NAD+ and FAD forming NADH+H+ and FADH2. and small amounts of ATP are formed through substrate phosphroylation
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What happens in stage 4 of catabolism?
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beings when NADH+ H+ and FADH2 enter the electron transport chain which is where most ATP production occurs by oxidative phosphorylation
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when additional glucose is needed, the hormone ?simtulates the breakdown of glycogen in the liver and the release of glucose in the blood
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glucagon
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When glucagon stimulates the breakdown of glycogen in the liver and releases glucose into the blood it is called _____
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glycogenolysis
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the breakdown of glycogen known as glycogenolysis represents _____
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stage 1 of carbohydrate catabolism
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The hormones ___ and ___ also sitmluate glycogenolysis in skeletal muscles
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cortisol and epinephrine
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Most glucose comes from the ingestion digestion and absorption of ____________.
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carbohydrate rich foods
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_____ involves a series of linked chemical reactions that comprise the electron transport chain which is located on the surface of inner mitochondrial membrane
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oxidative phosphorylation
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The energy need to phosphorylate ADP is provided by the oxidation of _________
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NADH+H+ and FADH2
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the metabolic pathways that splits glucose into two 3-carbon molecules called pyruvate
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glycolysis
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an intermediate product formed during metabolism of carbohydrates and some amino acids
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pyruvate
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when glucose enters stage 2 of carbohydrate catabolism what happens?
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glycolysis
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Glycolysis occurs in the cytoplasm of the cells; because oxygen is not required for any of these reactions glycolysis is a(an) ______metabolic pathway
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anaerobic
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What are the intermediate products that result from glycolysis?
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2 ATP and 2 molecules of NADH + H+ per glucose (which represents only a small amount of the total energy availbale in each glucose molecule due to the unbroken bonds of pyruvate)
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the direction pyruvate takes beginning stage 3 of carbohydrate metabolism is determined by ______
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oxygen avalibility; specifically whether pyruvate encounters anaerobic(oxygen-poor) or aerobic ( oxygen-rich) conditions in the cell
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Under relatively anaerobic conditions, pyruvate (end product of glycolysis) remains in the cytoplasm and is converted to ?, which is then released into the blood and taken up by the liver. In the liver it is converted to glucose by gluconeogenesis which is then able to under go glycolysis.
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lactate(lactic acid)
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an amphibolic metabolic pathway that oxidizes acetyl-CoA to yield carbon dioxide , NADH + H+ and FADH2 and ATP via substrate phosphorylation
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citric acid cycle
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the metabolic pathway that regenerates glucose by circulating lactate from muscle to the liver,where it undergoes gluconeogenesis
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the cori cycle
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the process whereby glucose is synthesized from non carbohydrate sources
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gluconeogenesis
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the final product of the citric acid cycle which becomes the substrate for the first reaction in this pathway
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oxaloacetate
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the first intermediate product in the citric acid cycle formed when acetyl-CoA joins with oxaloacetate
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citrate
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____ provides a means by which small amounts of ATP can be produced in the relative absence of oxygen.
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the cori cycle
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Because little ATP is produced, the Cori cycle cannot sustain ______ for very long. As a result extremely vigorous activity results in muscle fatigue relatively quickly. (sprints vs marathons?)
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physical exertion
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Under aerobic conditions, the 2 molecules of pyruvate move from the ___ to ____
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cytoplasm to mitochondria
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in the mitochondria pyruvate is chemically transformed into an intermediate product called ______
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acetyl-CoA (a two carbon unit attached to a compound called coenzyme A [CoA] )
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the transformation of pyruvate into acetyl-CoA is an irreversible rxn which requires several enzymes and vitamin B's including _________
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thiamin, niacin, pantothenic acid, and riboflavin
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the formation of acetyle CoA from pryuvate also results in the production of ? and ?
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carbon dioxide and NADH +H+
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under aerobic conditions acetyl-CoA is ready to enter into stage 3 of carbohydrate catabolism _______
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the citric acid cycle
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the citric acid cycle is also known as .....
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TCA - tricarboxylic acid cycle or Krebs cycle
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major pathway used during aerobic conditions consisting of chemical reactions that take place within mitochondria
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citric acid cycle
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The CAC is viewed in a circle because the product of the last reaction of the pathway ____ becomes the substrate for the 1st reaction ______
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oxaloacetate & citrate
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__________ is an anaerobic metabolic pathway that consists of a series of chemical reactions that splits a 6-carbon glucose molecule into 2 three carbon moelcules called pyruvate ( the fate of pyruvate depends on oxygen avalibility in the cell)
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glycolysis
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What happens to pyruvate under anaerobic conditions?
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it remains in the cytoplasm and is converted to (2)lactate which then enters into the cori cycle
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What happens to pyruvate under aerobic conditions?
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pyruvate is transported from the cytoplasm to the mitochonrida where it is converted into (2)acetyl-CoA and then enters into the citric acid cycle
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The ? is ametabolic pathway that involves both glycolysis and gluconeogenesis. under conditions of limited oxygen avalibility, the ? provides a means by which small amound of ATP can continue to be produced in the muscle
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The cori cycle
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Under aerobic conditions, pryuvate combines with coenzyme A to form ________
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acetyl - CoA
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metabolic pathway that generates intermediate products that can be used for both catabolism and anabolism
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amphibolic pathways
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high energy compound similar to ATP
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guanosine triphosphate (GTP)
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The CAC beings when acetyl-CoA combines with oxaloacetate to form ___. ( in this process Coenzyme A is released)
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citrate (citric acid)
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The formation of citrate due to the combination of acetyl-CoA and oxaloacetate is the first step in a series of chemical reactions that ultimately transfer the chemical energy contained in acetyl-CoA to ___ and ___
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NAD+ and FAD
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In the end CAC generates NADH + H+ and FADH2 which are highly energized coenzymes wheich enter __________ for ATP production
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electron transport chain
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In the CAC ATP is NOT formed directly, it is formed due to another high energy compound called ?? via substrate phosphorylation
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guanosine triphosphate GTP
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In the CAC as a whole, the oxidation of ____ molecules of acetyl-CoA produce ___ NADH + H+ and ___ FADH2 and ___ ATP's
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2, 6,2 and 2
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In total, the complete oxidation of 1 molecule of glucose (via glycolysis, the CAC, and oxidative phosphorylation) generates up to ___ ATP's -- depending on the source of glucose -- 10 NADH+H+, 2 FAHD2, and 4 ATP( formed by substrate phosphorylation )
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38
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for every 1 molecule of NADH+H+ there is an ATP yield of _____
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3 (approx 2.5)
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for every 1 molecule of FADH2 there is an ATP yiled of ___
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2(approx 1.5)
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Due to the major role of amino acids being to serve as the building blocks for preotins and other nitrogen contaiing compounds, amino acids are NOT considered major sources of energy, supplying less than ___ of our daily ATP needs
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10%
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Stage 1 of protein catabolism is the process of ? which breaks down protein into amino acids
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proteolysis (used in particular during times of sarvation in which stored protein is broken down primarily from the skeletal muscles)
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During proteolysis, the amino acids are taken up by the ?
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liver
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___ is the transfer of an amino group from an amino acid to an alpha-ketoacid usually alpha-ketoglutarate
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transamination
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The nitrogen containing amino group must first be removed from the central carbon which is done by transamination and the second step called deamination -- known as ?
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the 2nd stage of protein catabolism
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when the amino group from an amino acid is transferred to a compound called alpha-ketoacid forming a new amino acid
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first step of 2nd stage of protein catabolism : transamination
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The new amino acid formed by transamination is determined by the ________ of the alpha-ketoacid
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structure
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Normally in protein catabolism, the alpha-ketoacid used is _____ and it forms the amino acid glutamate.
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alpha-ketoglutarate
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The remaining carbon skeleton from the amino acid after transamination is now itself an alpha-ketoacid and is used as ______
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an energy source
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_____ the removal of an amino group from an amino acid
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deamination
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occurs primarily in the liver, a process which removes the amino group from the newly formed amino acid, leaving another alpha-ketoacid (in this case alpha-ketoglutarate is formed when the amino group is removed from glutamate)
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2nd step of the 2nd stage of protein catabolism : deamination
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The amino group removed from the newly formed amino group is converted to a compound called ?
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ammonia - b/c of its toxicity it is quickly converted to a less toxic UREA which is released into the blood
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Urea is removed from the blood by the ___ and excreted in the urine.
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kidneys
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Deamination also produces _____, which undergoes oxidative phosphorylation through the electron transport chain
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NADH + H+
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Depending on the needs of cells, the alpha-ketoacid can be _______ or ______
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metabolized for energy, or used to synthesize glucose or fatty acids
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Because R-groups determine the structure of the alpha-ketoacid, some of them can be converted to ____ or ____ or ____
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acetyl-CoA, pyruvate, or intermediate products of the citric acid cycle -- this allows alpha-ketoacids to enter into the CAC at various points
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follow the completion of transamination and deamination the alpha-ketoacid is prepared to enter the 3rd stage of protein catabolism
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the citric acid cycle
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No matter where a-ketoacids enter the CAC they are oxidized to produce the reduced coenzymes _____ and ____
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NADH+H+ and FADH2
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NADH+H+ and FADH2 from the CAC then enter the final 4th stage of protein catabolism ???
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the electron transport chain
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Because a-ketoacids produced from diff a.a. enter the CAC at different points the ________ produced from them varries
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total number of ATP
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The breakdown or proteins into peptides or amino acids
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proteolysis
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the structure remaining after the amino group has been removed from an amino acid
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a-ketoacid
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___ - the first stage of lipid catabolism - is catalyzed by the enzyme hormone-sensitive lipase, whose activity is stimulated by rising levels of pancreatic hormone glucagon during periods of low glucose avalibility
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lipolysis
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the enzymatic breakdown of triglycerides into glycerol and fatty acids by hormone sensitive lipase
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lipolysis
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to use amin acids for a source of energy, the amino grup is removed in two steps: ? and ?
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transamination and deamination
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|
|
_____ is also stimulated by low levels of insulin, exercise, and during times of stress by the adrenal hormones epinepherine and cortisol
|
hormone sensitive lipase
|
|
|
_____ released during lipolysis can be converted to pyruvate or glucose and further used for energy as well
|
glycerol
|
|
|
series of chemical reactions that breaks down fatty acids to molecules of acetyl-CoA
|
B-oxidation (beta-oxidation)
|
|
|
stage 2 of lipid(triglyceride) catabolism - takes place in th emitochondria and involves the arduous process of disassembling fatty acids into 2-carbon subunits
|
B-oxidation
|
|
|
before B-oxidation takes place the fatty acid must be activated in the cytoplasm by the addition of _______to its carboxylic acid end
|
coenzyme A (CoA)
|
|
|
after the activation of the fatty acid due to added CoA, the fatty acid can be transported from the cytoplasm across the outer mitochondrial membrane by a _____ molecule
|
carnitine
|
|
|
molecule found in muslce and live rcells that transports fatty acids across the mitochondrial membrane
|
carnitine
|
|
|
it takes ___ molecules of glutamate to make one molecule of urea
|
2
|
|
|
B-Oxidation takes place in all cells but ? which lack the organelles required for this metabolic process
|
brain and red blood cells
|
|
|
_______begins when a series of enzymes systematically cleave off a 2 carbon subunit from the fatty acid's carboxylic end which results in the synthesis of acetyl-CoA
|
B-oxidation
|
|
|
The fatty acid is continually broken down through the reactivation of FA by addition of CoA which is then cleaved again, done ___ carbons at a time
|
2
|
|
|
Each 2 carbons that are cleaved during B-oxidation releases electrons and hydrogen ions which are used to form _____and ____
|
1 NADH+H+ and 1FADH2
|
|
|
B-Oxidation of 18-carbon fatty acid requires 8 cleavages producing _____
|
9 acetyl-CoA molecules, 8 NADH+H+ and 8 FADH2
|
|
|
the reduced coenzymes resulting from B-oxidation generate ____
|
ATP
|
|
|
Stage 3 of lipid catabolism begins when molecules of acetyl-CoA result from B-Oxid enter into the __________
|
citric acid cycle
|
|
|
_________ are generated per acetyl-CoA
|
total of: 3 NADH+H+, 1 FADH2, and 1ATP(produced by GTP via substrate phosphorylation)
|
|
|
Stage 4 of lipid catabolism: reduced coenzymes produced via B-Oxid and the citric acid cycle enter into the _________
|
electron transport chain
|
|
|
An 18-carbon fatty acid produces considerably more ATP than a single molecule of glucose ( 4kcal per g carb vs 9kcal per g fat)
|
38 ATP vs 148 ATP
|
|
|
Anabolism tends to take place in ______ where catabolism primarily takes place in ______
|
cytoplasm, mitochondria
|
|
|
During times of energy abundance, anabolic pathways convert energy yielding nutrients into forms that can be stored - ? and ?
|
glycogen and triglycerides
|
|
|
Anabolic pathways also help when the diet is poor and doesnt provide right amount of certain nutrients by providing ___________
|
alternate routes for their synthesis
|
|
|
An average person had ? liver glycogen and ? muscle glycogen - enough glucse to provide energy for 8 to 12 hours.
|
70 g and 200g
|
|
|
glucose breakdown forming 2 molecules of pyruvate; anaerobic energy metabolism. all tissues. amphibolic
|
glycolysis
|
|
|
glucose synthesis from noncarbohydrate sources during conditions of fasting and stress. liver and kidneys. anabolic
|
gluconeogenesis
|
|
|
breakdown of glycogen for glucose production. liver and muscle. catabolic
|
glycogenolysis
|
|
|
formation of glycogen. liver and muscle. anabolic
|
glycogenesis
|
|
|
synthesis of fatty acids and triglycerides. liver and adipose tissue. anabolic
|
lipogenesis
|
|
|
breakdown of triglycerides to fatty acids and glycerol. adipose and muscle tissue. catabolic
|
lipolysis
|
|
|
breakdown of fatty acids to acetyl-CoA. liver and muscle. catabolic
|
B-Oxidation
|
|
|
formation of ketones, an alternative energy source from acetyl-CoA. liver. anabolic
|
ketogenesis
|
|
|
breakdown of protein to amino acids. muscle. catabolic
|
proteolysis
|
|
|
a central metabolic pathway that oxidizes acetyl-CoA to yield carbon dioxide, NADH+H+, FADH2, and GTP. all tissues but red blood cells. amphibolic
|
citric acid cycle
|
|
|
a coupled process whereby reduced coenzymes NADH+H+ and FADH2 are oxidized to NAD+ and FAD and ADP is phosphorylated to ATP. All tissues but red blood cells. N/A
|
oxidative phosphorylation
|
|
|
Because there is a limit to how much glycogen can be stored, ? also promotes the uptake of excess glucose by adipose tissue where it can be turned into fatty acids and ultimately triglycerdies this process is known as __________
|
insulin & lipogenesis
|
|
|
The conversion of glucose to fatty acids is _______
|
irreversible
|
|
|
What happens through the entire process of lipogenesis?
|
glucose is broken down via glycolysis into 2 pyruvate which is then broken down into 2 molecules of acetyl-CoA. Next molecules of acetyl-CoA are joined together to make a fatty acid via fatty acid synthesis. Afterwards 3 fatty acids are attached to a molecule of glycerol to make a triglyceride
|
|
|
The entire process of lipogenesis requires approximately _____ % of the energy originally in the glucose molecule.
|
20-25%
|
|
|
excess glucose and amino acids can be used to synthesize fatty acids which subsewuently join with a molecule of glycerol to make _____
|
triglyceride
|
|
|
amino acids not used for protein synthesis are taken up by the liver, converted to ? and used to form triglyceride molecules
|
fatty acids
|
|
|
The energy required to convert amino acids to triglycerides is even greater than that reuired to convert glucose to triglycerides. This is due to the nitrogen containing amino group having to experience _______ and _____ afterwards allowing the reamaing structure to be converted to acetyl-CoA
|
transamination and deamination
|
|
|
To ensure that brain and red blood cells as well as other tissues of the body have a contunual supply of glucose, small amounts of glucose are stored as ______ in the _______
|
glycogen in the liver and skeletal muscles
|
|
|
When glycogen stores are depleted, noncarbohydrate molecules are transforming into glucose by _____________
|
various anabolic pathways called gluconeogenesis
|
|
|
_________ occurs primarily within the liver cells, and to a liesser extent kidney cells
|
gluconeogenesis
|
|
|
What are the noncarbohydrate sources used to gluconeogenesis ?
|
most amino acids, lactate, and glycerol
|
|
|
For the amino acids, lactate, and glycerol to be used in gluconeogenesis what must happen?
|
these compounds are first converted to oxaloacetate and then to glucose. The energy needed to fuel these rxns comes from ATP and the oxidation of NADH+H+ to NAD+
|
|
|
Gluconeogenesis is an energy intensive process; stimulated by the hormones _______ and ______ ; ____ inhibits gluconeogenesis
|
glucagon and cortisol; insulin
|
|
|
Amino acids used to generate glucose via gluconeogenesis are referred to as glucogenic amino acids; the two that mainly assist in this is _________ and ________
|
leucine and lysine
|
|
|
There are several routes that glucogenic amino acids can be converted to glucose by, all involving ___________, and _________
|
removale of the amino group via transamination and deamination and the transformation of the remaining strucutre to oxaloacetate
|
|
|
During glucogenogenesis from amino acids first, the carbon skeleton of some amino acids is converted to pyruvate and then to oxaloacetate. Oxaloacetate (a 4 carbon compound) loses 1 carbon which combines with oxygen to form carbon dioxide. This results in the 3-carbon compound ____________, which then follows many steps of glycolysis but in reverse.
|
phosphoenolpyruvate (PEP)
|
|
|
it take ___ molecules of phosphoenolpyruvate(PEP) to form 1 molecule of glucose
|
2
|
|
|
The reactions that take place during gluconeogenesis of amino acids require many coenzymes that are derived from ______ and ______
|
the B vitamins: Biotin, riboflavin, and niacin & Vitamin B6
|
|
|
During starvation when little carbohydrates are consumed the supply of ________ becomes depleted
|
oxaloacetate
|
|
|
The depletion of oxaloacetate during times of starvation occurs because _________
|
oxaloacetate is diverted to gluconeogenic ( glucose forming) pathways to produce much needed glucose for cells that require it for ATP production
|
|
|
Due to depletion of oxaloacetate during times of starvation the CAC is unable to operate at full speed which prevents acetyl-CoA forming during B-oxidation to enter into the CAC. as a result the body uses an alternate form of energy _________
|
ketones through ketogenesis
|
|
|
anabolic process provides the body with an important source of energy during period of low glucose avalibility
|
ketogenesis
|
|
|
ketones can be produced from some ______ and _______
|
amino acids and fatty acids
|
|
|
____ are organic compounds used as an energy source during starvation fasting low carbohydrate diets or uncontrolled diabetetes and _____ regers to the metabolic pathways used to produce them
|
ketones
|
|
|
amino acids that can be used to make ketones
|
ketogenic amino acids
|
|
|
Molecules of acetyl-CoA join together to form ketones such as _______ , ________, _______
|
acetoacetate, B-hydroxybutyrate, and acetone
|
|
|
The production of ketones from acetyl-CoA occurs mostly in the ____ and is stimulated by ______.
|
liver and glucagon
|
|
|
The processes of ______ and ______ typically occur simultaneously.
|
gluconeogenesis and ketogenesis
|
|
|
________ is important because some tissues such as muscle, brain, and kidney have special enzymes that allow them to use ketones for ATP production.
|
ketogenesis
|
|
|
_____ can spare the body from having to use amino acids to synthesze large amounts of glucose via gluconeogenesis
|
ketones
|
|
|
When ketone production exceeds ketone us high levels of ketones in the blood are reached forming a condition called ______
|
ketosis
|
|
|
can occur during prolonged fasting, consumption of very low carbohydrate diets, strenuous exercise and some diseases such as type 1 diabetes
|
ketosis
|
|
|
servere ketosis is called ? that can cause a variety of complications including lowered blood pH nausea coma and in extremes death
|
ketoacidosis
|
|
|
accumulation of ketones in body tissues and fluids
|
ketosis
|
|
|
a rise in ketone levels in the blood causing the pH of the blood to decrease
|
ketoacidosis
|
|
|
The relative activity of anabolic and catabolic pathways is determined by what?
|
the availability of the substrates, intermediate compounds, and energy needs
|
|
|
Amino acids, glucose, fatty acids, and glycerol can be converted to _______ and/or _______. Depending on energy needs, these comounds enter either anabolic or caatabolic pathways
|
pyruvate and/or acetyl-CoA
|
|
|
During times of excess acetyl-CoA can be converted to _______ to then form _______
|
fatty acids - triglycerides
|
|
|
When energy is needed acetyl-CoA enters __________ and is oxidized to carbon dioxide, releasing energy in the process. Electrons and hydrogen ions are transferred to coenzymes FAD and NAD+ forming FADH2 and NADH+H+
|
the citric acid cycle
|
|
|
During times of energy excess ______ pathways predominate. amino acids , glucose, and fatty acids are converted to protein, glycogen, and triglycerides
|
anabolic pathways
|
|
|
During times of energy need, ______ predominates, breaking down proteins, glycogen, and triglycerides to amino acids, glucose and fatty acids
|
catabolic pathways
|
|
|
________ and __________ predominate when there is a lack of avalible glucose. Oxaloacetate can leave the citric acid cycle and is used to synthesize glucose
|
gluconeogenesis and ketogenesis
|
|
|
After a meal, ________ favor the synthesis and storage of glycogen, protein and triglycerides.
|
anabolic pathways
|
|
|
After a period of time without eating, the body is primarily in a _______ state relying on ATP generated from the breakdown of the body's stored energy reserces.
|
catabolic
|
|
|
_________ determines the balance of anabolic and catabolic activity
|
energy avalibility
|
|
|
_____ may be the single most influencial factor modulating energy metabolism.
|
energy avalibility
|
|
|
What are the four nutritional states which are based upon how energy availability influences energy meatbolism?
|
1.asoprtive state
2. postabsorptive state 3. acute starvatoin 4. prolonged starvation |
|
|
The relative concentration of insulin is higher than glucagon, favoring energy storage; blood glucose is elevated
|
absorptive state
|
|
|
What happens in the absorptive state
|
first four hours after a meal, post prandial period; during this state absorbed nutrients enter the blood, stimulating the realse of insulin and inhibiting the relase of glucagon, affecting energy metabolism in the liver, adipose tissue, and skeletal muscle. many major anabolic pathways occur . glucose is major source of energy; as long as there is suffiecient oxygen most ATP produced provided by glycolysis, citric acid cycle, and electron transport chain
|
|
|
insulin levels decrease, and glucagon increases. Blood glucose decresases. liver glycogen broken down for a source of glucose. increase use of fatty acids for energy.
|
postabsorptive state
|
|
|
What happens during the postabsorptive state?
|
periods between meals when no nutrients are being absorbed; begins about hours after the last intake of food, when insulin secretion declines and the release of glucagon increases. the body's cells rely heavily on energy supplied by the brakdown of stored energy . BGL maintained by liver glycogen via glycogenolysis .
|
|
|
Most glucose, ______% , used by body tissues during the postabsorptive state comes from liver glycogen
|
75
|
|
|
During the postabsoprtive state most cells continue to produce ATP via glycolysis, citric acid cycle, and electron transport chain; however, many cells increase their use of _________ as an energy source during this time to ensure that there is enough glucose for red blood cells and the central nervous system.
|
fatty acid
|
|
|
Declining levels of insulin stiulates lipolysis and the subsequent release of ____ into the circulation during postabsorptive phase
|
fatty acids
|
|
|
relative concentration of glucagon is higher than insulin, liver glycogen stores are depleated, glucose is supplied mainly by gluconeogenesis, stored triglycerides are broken down with an increase in the use of fatty acids for energy. ketone formation(ketogenesis) increases
|
acute starvation
|
|
|
defined as the first five days of fasting or minimal food intake, beginning 24 hours after last meal
|
acute starvation
|
|
|
what happens during acute starvation?
|
body's ready supply of glucose has deminished significantly, insulin to glucagon ratio demimishes further, priority is to supply the body's nervous system and red blood cells with sufficient glucose, glucose must now be provided by non carbohydrate substances via gluconeogenesis. Muscles contribute by supplying amino acids, lactate, and glycerol - used by the liver to generate small amounts of glucose
|
|
|
The loss of lean tissue during early stages of acute starvation reduces the body's
??? - important b/c it helps the body to prolong survival if starvation continues |
totaly energy requirements
|
|
|
During acute starvation, the body relies more and more on _________ for a source of energy
|
mobilized fatty acids
|
|
|
During acute starvation when glucose is severely limited and oxaloacetate is being removed from the citric acid cycle to support gluconeogenesis, cells cannot copmletely oxidize acetyl-CoA and _______ pathways are stimulated
|
ketogenic
|
|
|
_____ helps preserve lean body tissue beucase hte body doesnt have to rely as extensively on gluconeogenesis to support energy requirements
|
ketogenesis
|
|
|
food deprevation lasting longer than a week, during this time only red blood cells continue to rely only on glucose as a substrate for ATP production(they dont have organelles which can metabolic fatty acids and ketones for energy), remaining parts of the body and tissues rely soley on ketones as a major source of energy. ketogenesis is further stimulated. and when stored fats become extremely limited the body has no choice but to break down muscle tissue as the only remaining source of glucose and energy.
|
prolonged starvation
|
|
|
what happens in prolonged starvation?
|
• Food deprivation lasting longer than 1 week
• Only red blood cells rely solely on glucose as a substrate for ATP production • Reliance on ketones • When fat is limited, muscle breakdown occurs |
|
|
What were the outcomes of the keys starvation experient which subjects were placed on a semi-starvation diet for 6 months?
|
o ~24% body weight loss
o Total energy requirements decrease o Lethargy, lacked endurance, diminished strength o Depression, emotional instability o Lack of grooming o Food cravings increased |
|
|
The use of various energy metabolism pathways by the body is affected by _____________________.
|
what howmuch and how frequently food is consumed
|
|
|
The _____ of energy metabolism pathways enables the cells to respond to a variety of different circumstances to ensure that energy (ATP) needs are always met.
|
versatility
|
|
|
The body's ability to cope with extreme situations such as prolonged fasting, and startvation, demonstreates the extent to which energy metabolism pathways can respond to preserve life.
|
true
|
|
|
The form of alcohol found in alcoholic beverages is a molecule called _____ which has a chemical formula of C2H5OH
|
ethanol
|
|
|
Alcohol isnt considered a nutrient but it provides ____ kcal per gram of energy
|
7
|
|
|
yeast converts sugar(glucose) to pyruvate via __________ . The end products are 2 molecules of pyruvate and 2 molecules of NADH+H+
|
glycolysis
|
|
|
Explain the process of fermentaion step by step via each metabolic pathway.
|
Glucose to 2 pyruvate via glycolysis, 2 pyruvate to 2 ethanol via fermentaion
|
|
|
The process of ________ converts each pyruvate molecule to ethanol. The end product of ? are ethanol, CO2, and NAD +
|
fermentation
|
|
|
organic compound containing one or more hydroxyl groups attached to carbon atoms
|
alcohol
|
|
|
alcohol produced by chemical breakdown of sugar by yeast
|
ethanol
|
|
|
process used to make concentrated alcohol beverage by condensing and collecting alcohol vapors
|
distillation
|
|
|
what determines rate of alcohol absorption?
|
1.presence of food in the stomach(dilutes alcohol and slows down gastric emptying) - when no food is present pyloric sphincter remains open allowing alcohol to easily be absorbed
2.concentraion of alochol - drinks with high alcohol conc greater than 30%/60 proof delay gastric emptying and slows absorption |
|
|
When alcohol is consumed it requires no digestion and is readily absorbed by ________ into the blood. Some is absorbed in the stomach but most alcohol absorption takes place in the ________
|
simple diffusion. small intestine
|
|
|
once absorbed alcohol enters the blood stream and circulates through out the body. the amount of alcohol in the blood is called ?
|
blood alcohol concentration
|
|
|
The rate of alcohol metabolism is ______ compared to the rate of absorption
|
slower
|
|
|
Alcohol is unsual in composition being ________ and ______.
|
water soluble and lipid soluble
|
|
|
As a ____ soluble molecule alcohol readily crosses cell membranes.
|
lipid
|
|
|
As a _____ soluble molecule alcohol becomes distributed in the water-filled environments inside (intracellular) and outside (extracellular) of cells.
|
water
|
|
|
If two individuals were to ingest the same amounts of alcohol the ______ individual would have a lower BAC
|
the leaner - because lean tissue has more water associated with it than adipose tissue, this allows alcohol within the blood to diffuse into lean tissue until equilibrium is reached while adipose tissue doesnt enable alcohol to be absored resulting in high concentrations of alcohol within the blood
|
|
|
What influences BAC?
|
body composition and size
|
|
|
o Women have less water in their body more adipose that composition effects the blood alcohol levels
o Women smaller than men o Women don’t have the enzymes that metabolizes alcohol at low intake o Men metabolism more alcohol in gastric tissues than women can All exmaples of what? |
influence of body composition and size on BAC
|
|
|
What are the effects of alcohol on the central nervous system?
|
1. depressant-sedates brain activities
2.causes dis-inhibition - inhibitory effect of alcohol on portions of the brain that control thoughts and behaviors causing a temprary loss of inhibition (outgoing friendly relaxed) impares judgement and reasoning |
|
|
The body can metabolize ? oz of pure alcohol per house
|
0.5
|
|
|
What are the 2 major pathways used to metabolize alcohol?
|
alcohol dehydrogenase(ADH) pathway=low intake and Microsomal ethanol-oxidizing system(MEOS)=high intake
|
|
|
Small amounts of alcohol are eleminated by the kidneys, skin and lungs, the majority of alcohol is broken down by the ________
|
liver
|
|
|
the primary metabolic pathway that chemically breaks down alcohol in the liver
|
alcohol dehydrogenase pathway
|
|
|
an enzyme found mostly in the cytoplasm of liver cells that metabolizes ethanol to acetaldehyde
|
alcohol dehydrogenase(ADH)
|
|
|
an enzyme that converts acetaldehyde to acetic acid
|
acetaldehyde dehydrogenase
|
|
|
What causes the unpleasant side effects associated with alcoholic drinking? (hangover)
|
if TOXIC acetaldehyde accumulates some will pass from the liver into the blood which causes headaches nasea and vommiting
|
|
|
Why is some alcohol metabolized in the sotmach?
|
ADH is also produced by the gastric cells of the stomach allowing some alcohol to be metabolized yielding 7kcal/g
|
|
|
What are the two steps within the Alcohol Dehydrogenase Pathway?
|
1. enzyme alcohol dehydrogenase(ADH) converts alcohol to acetaldehyde generating NADH+H+
2. the enzyme acetaldehyde dehydrogenase (ALDH) converts acetaldehyde to acetic acid |
|
|
The second step of ADH pathway requires ____ for the transfer of hydrogen and forms ______. Acetic acid combines with a molecule of coenzyme A to form ______ which can enter into the citric acid cycle and be metabolised further.
|
NAD+ , NADH+H+, acetyl-CoA , citric acid cycle
|
|
|
The metabolism of ONE molecule of acetic acid yield approximately ____ ATP & The metabolism of acetyl-CoA(~2ATP?) via citric acid cycle yields additional energy (ATP)
|
6
|
|
|
o Affects enzymatic activities of ADH and ALDH
o Causes difficulty in metabolizing alcohol o Seen mostly in Women & Asians |
genetic alterations of alcohol metabolism
|
|
|
Women tend to have lower ____ activity in gastric cells then men and may have a lower tolerance for alcohol. also may be why women are more likely to develop alcohol related health probelsm
|
ADH
|
|
|
ADH pathway takes place in the fluid filled _____ of the cell.
|
cytosol
|
|
|
The MEOS takes place in side the _______
|
microsomes
|
|
|
a pathway used to metabolize alcohol when it is present in high amounts
|
microsomal ethanol-oxidizing system MEOS
|
|
|
___ helps to prevent alcohol from reaching dangerously high levels in the blood
|
MEOS
|
|
|
Why/how do some people develop a tolerance to alcohol?
|
the components of the MEOS pathway are up-regulated in response to frequent intoxication - mainly heavy drinkers
|
|
|
people who metabolize alcohol quickly allowing them to drink large amounts before feeling intoxicated have developed
|
tolerance to alcohol
|
|
|
Response to repeated drug exposure that results in a reduced effect
|
tolerance
|
|
|
MEOS is also used to metabolize other drugs besides alcohol. for this reason, heavy drinkers often develop ________; developing a tolerance to alcohol also builds up a tolerance to certain other drugs
|
cross tolerance
|
|
|
The need to metabolize alcohol often overrides the need to metabolise other drugs gives rise to what danger
|
you shouldnt drink and take drugs at the same time because you body will only metabolise the alcohol allowing the drug to reach dangerously high levels of toxicity in the blood
|
|
|
_______ small spherical vesicles embedded within the endoplasmic reticulum
|
microsomes
|
|
|
the MEOS uses __________ and _______ to convert alcohol to acetaldehyde.
|
oxygen and NADH+H+
|
|
|
The ADH pathway yields NADH+H+ while MEOS uses actually ______ to form acetaldehyde
|
energy (NADH+H+)
|
|
|
Much of the energy release from alcohol when metabolized during MEOS is lost as ____ instead of supplying the body with energy; this may explain why heavy drinkers experience unexpected weightloss
|
heat
|
|
|
What impact does alcohol metabolism have on the liver?
|
1.the accumulation of acetaldehyde damages the liver & impairs its function
2. raises NADH + H+ levels and lowers NAD+ within the liver (NAD+ is needed to convert pyruvate to acetyl-CoA, when unavaible pyruvate is converted to lactate) 3. high levels of lactate within the blood interferes with the body's ability to excrete uric acid in the urine - rising levels of uric acid in the blood can create a condition called gout |
|
|
caused by rising levels of uric acid in the blood; excess production and deposit of uric acid crystals in joints
|
gout
|
|
|
a condition caused by excess alcohol consumption characterized by the accumulation of triglycerides in the liver
|
fatty liver
|
|
|
What are the effects of alcohol on lipid metabolism in the liver?
|
1. lipids accumulate in the liver: due to decreased fatty acid breakdown via B-oxidation, increased uptake of fatty acids from the blood, increased fatty acid synthesis and triglyceride formation (lipogenesis) , and decreased transport of triglycerides from the liver into the blood
2. the high conc of NADH+H+ causes the amount of acetyl-CoA entering citric acid cycle to decrease and instead acetyl-CoA sytnehsize fatty acids and then form triglycerides , the lipogenic effects of chronic and heavy alcohol comsumption cause triglycerides to accumulate in the liver creating a coniditon called fatty liver |
|
|
What are the two forms of vitamin A which are effected by alcohol metabolism in the liver?
|
retinol and retinal
|
|
|
Retinol is an alcohol and metabolised by ADH to form _____
|
retinal
|
|
|
_____ is the alcohol form of vitamin A
|
retinol
|
|
|
____ is the aldehyde form of vitamin A
|
retinal
|
|
|
_____ is the form of vitamin A needed for night vision
|
retinal
|
|
|
When a person drinks heavily alcohol is given preferiential acess to ADH, thus ______.
|
less retinal is made by the body, leading to vision problems esp at night
|
|
|
What are the health benefits associated with moderate alcoholic drinking?
|
extends years of life and lowers risk of: cardiovascular disease(40%), gallstones, agerelated memory loss, and type 2 diabetes
|
|
|
What is considered moderation for men and women when consuming alcoholic beverages>
|
up to 1 drink/day for women and up to 2 drinks a day for men
|
|
|
What is a standard drink?
|
12 floz beer, 5 floz wine, 1.5 fl oz of liqour, ~12-14 grams of alcohol
|
|
|
under moderal alcohol consumption 1-2 alcoholic drinks perday decrease CVD 25-40% by: _____.
|
increases HDL concentrations, decreases protein fibrinogin which promotes blood clot formation, and increases levels of an enzyme that dissolves blood clots, and alcohol has an anti-inflammatory effect
|
|
|
• Alcohol increases the risk of mouth and esophageal cancer, especially among those who smoke
• Alcohol can damage the heart muscle, increasing the risk of alcoholic cardiomyopathy |
are associated with risks of heavy alcoholic drinking
|
|
|
The liver is the primary organ of alcohol metabolism. Heavy drinking cause fat accumulation in the liver. After years of heavy serious conditions can result in the liver such as ______ and ______
|
alcoholic hepatitis and cirrhosis
|
|
|
inflammation of the liver caused by chronic alcohol abuse; typically has enlarged and swollen liver due to accumulation of fat in the liver which obstructs blood flow depriving liver cells of oxygen and nutrients
|
alcoholic hepatitis
|
|
|
the formation of scar tissue in the liver caused by chronic alcohol abuse; developed by 10-15% of heavy drinkers
|
cirrhosis
|
|
|
Heavy drinking can damage the pancreas and cause ?
|
pancreatitis which can further lead to pancreatic cancer
|
|
|
Alcohol interfers with digestion, absorption, use and excretion of nutrients. Chronic alcohol intake can lead to ______
|
malnutrition, cancer, and heart disease
|
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If consuming a proper diet during drinking, alochol can ______; however alcoholic tend to eat poor diets
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increase energy intake
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Heavey drinking leads to decreased nutrient availability and impaired nutritional status via _________
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primary and secondary malnutrition
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reduce absorption of nutrients due to essiential nutrient deficiences
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primary malnutrition
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the interference alcohol creates with digestion, absorption, utilization, and excretion of various nutrients leads to
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secondary malnutrition
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when alcohol accounts for more than ___% of total eneryg, micronutrient intakes are likely to be inadequate
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30
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making up information; a falsification of memory occurring in clear consciousness in association with an organically derived amnesia
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confabulation
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fleeting, and invariably provoked by questions probing the subject’s memory – sometimes consisting of “real” memories displaced in their temporal context
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momentary (provoked) confabulations
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characterised by the spontaneous outpouring of irrelevant associations – sometimes bizarre ideas, which may be held with firm conviction
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fantastic (spontaneous) confabulations
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• Patients who have suffered brain damage or lesions, especially to the Prefrontal cortical regions, may have confabulation of memories as a symptom.
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true
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realted to thiamin deficiency and is characterized by impairment of short-term memory, poormuscle coordination, and confusion;
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Wernicke-Korsakoff syndrome
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A person could try to eat properly but doesn’t matter b/c they can no longer metabolize it therefore the only way to help is at the hospital being injected without having to go through metabolism (thiamin can't just be injected after chronic intake of alcohol b/c you have now developed impaired absorption and altered metabolism)
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example of secondary malnutrition - alters the way digestion absorption utilization and excretion occur
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alcoholic liver diease associated with low levels of vitamin A in plasma, decreased sytnehsis of retinol binding protein needed to circulate vitamin A, decreased conversion of retinol to retinal, reduced vitamin A absorption with pancreatic disease; yields impaired vision and impaired ability to see in dim light
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the effect of alcohol on fat soluble vitamin A
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alcoholic liver disease impairs ability to convert vitamin D to its active form calcium, pancreatic impairment leads to malabsorption; yields increased suceptibility to bone fractures and osteoperosis
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the effect of alcohol on fat soluble vitamin D
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pancreatic impairment leads to malaboroption; yields nerve damage, tunnel vision, fragility of cell membreanes
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effects of alcohol on fat soluble vitamin E
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pancreatic impairment leads to malabosorption, and alcoholic liver disease impairs ability to synthesize vitamin K -dependent factors needed for blood clot formation; yields brusing and prolonged bleeding
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effects of alchol on fat solulble vitamin K
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o Hypertension
o Stroke o Cardiac arrhythmia o Cardiomyopathy Apoptosis o Sudden cardiac death Are all associated with? |
long term heavy alcoholic drinking
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Increased risk from 7 drinks/day for 5 years or more
o Interferes with digestion & nutrient absorption o Causes poorly regulated blood glucose levels |
pancreatitis - inflammation of the pancreas
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condition that results when the heart muscle weakens in response to heavy alcohol consumption
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alcoholic cardiomyopathy
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irregular heartbeat caused by high intakes of alcohol
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cardiac arrhythmia
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consumption of 5 + drinks for males and 4+ drinks for women with the intent to become intoxicated
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binge drinking
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Who should avoid alcohol completely?
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adolesence, children, women of child bearing age who may become pregant, lactating women, pregnant women, individuals that cannot restrict alcohol intake, those taking medications, and individuals with specific medical conditions
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How does the DGA adress drinking?
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promoting drink only in moderation to those who are allowed, and recognize that some people should completely avoid alcohol consumption
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can occur when a cell becomes damaged by alcohol and or acetaldehyde, over time causing the heart muscle to weaking making it difficult for the heart to contract foricibly; there fore blood flow to vital organs like lungs liver kidneys and brain is reduced
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apoptosis "programmed cell death"
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