Biochemistry Review Pa

Front 1

How does the body produce energy?

Back 1

Energy released during the breakdown of glucose and other molecules to CO2 and H2O is released gradually to form energy-containing packets of ATP molecules. ATP is then used as an energy source in driving many biochemical reactions.

Front 2

Name the forms of energy storage for ATP?

Back 2

Glycogen and Trigylcerides

Front 3

List the general principle pertaining to the direction of Chemical reactions?

Back 3

Chemical reactions proceed in the direction in which the bonds are more stable and in which energy is released
“Energy is released as unstable bonds are broken and more stable ones are formed.”

Front 4

Define Reducing Agent

Back 4

Supply hydrogen atoms, or e- in chemical reactions
Ex NADH, NADPH, FADH2

Front 5

Define Oxidizing Agent

Back 5

Receive hydrogen atoms or electrons

Front 6

Define First law of Thermodynamics:

Back 6

The conservation of energy:
The total energy on one side of an equation equals the total on the other
Energy can neither be created nor destroyed

Front 7

Define Second Law of Thermodynamics:

Back 7

Things tend to proceed from a state of order to a state of disorder.
Entropy being a term used to describe the degree of disorder
Low entropy ->high entropy

Front 8

Define Enzyme:

Back 8

Special proteins that catalyze chemical reactions

Front 9

Define Oxidative Phosphorylation

Back 9

Oxidation by a series of reactions requiring O2 at the end COUPLED WITH phosphorylation of ADP to ATP

Front 10

Describe how chemical reactions in the human body seem to conflict with the 1st and 2nd law of thermodynamics as well as how they do comply.

Back 10

Chemical reactions often proceed from simple molecules to more complex ones. The body grows and is maintained vs decays. Appears to be greater order then disorder. Although chemical synthesis proceeds partly to produce greater order, in structure and function, they are accompanied by an even greater disorder produced in the dissipation of energy.

Front 11

List the determinants of the rate of chemical reactions in the body

Back 11

The energy of activation, temperature, concentration of substrate, and concentration of product.

Front 12

Describe why two way enzymatic reactions do not compete against one another

Back 12

The reactions each way are different, containing different substrates depending on the direction, each way uses a different enzyme

Front 13

Understand the mechanism behind malignant hyperthermia

Back 13

When two-way reactions inappropriately simultaneously occur in the human body, with excess heat production to the extent of death

Front 14

Define the differences between enzymes and hormones in chemical reactions

Back 14

Enzyme-Control the reaction rate
Hormones-Directly or indirectly affect the degree of enzyme synthesis or activation

Front 15

List the key fuel that runs the main Powerhouse Farris Wheel (Kreb’s Cycle)

Back 15

Acetyl CoA, which is formed when glucose is broken in half

Front 16

List the key fuel produced by the Kreb’s Cycle

Back 16

ATP

Front 17

List the key element needed to run the Kreb’s Cycle

Back 17

O2, because without it oxidative phosphorylation could not occur and the fermentation process would be the result yielding carbon dioxide and lactic acid.

Front 18

List the total number of ATP molecules generated by gylcolysis and the Kreb’s cycle

Back 18

36
Glycolysis (uses 2, produces 4->2)
Krebs/oxidative phosphorylation (30)
Glycerol 3 Phosphate shuttle (4)

Front 19

List the source of energy for the Kreb’s Cycle during periods of starvation

Back 19

Amino Acids: this is however bad because it leads to the breakdown of important protiens

Front 20

Understand the difference between anaerobic and aerobic metabolism

Back 20

If not enough O2, you need a way to replenish NAD+. There is no oxidative phosphorlation so, pyruvate transforms to lactate. If anaerobic, then only 2 ATP made.

Front 21

List the organ systems involved in the glycolysis process of the Main Powerhouse

Back 21

Occurs throughout the body

Front 22

List the organ system(s) involved in the gluconeogenesis of the Main Powerhouse

Back 22

Mainly the liver, sometime the kidneys

Front 23

List the sections of Biochemistry and the intracellular organs where they occur

Back 23

Nucleus-DNA and RNA synthesis

Cytosol-Glycolysis, protien synthesis, HMP shunt, part of gluconeogenesis, fatty acid synthesis

Golgi Apperatus- synthesis (glycosylation) and packageing of complex molecules including glycolipids, glycoprotiens and lipoprotiens, carbohydrate synthesis

Mitochondria- Kreb’s Cycle, fatty acid oxidation, formation of Acetyl CoA, part of gluconeogenesis

Front 24

List the Chemical Formula for glucose

Back 24

C6H12O6

Front 25

List 4 types of Carbohydrates

Back 25

Monosaccharides- CHOs that cannot be hydrolyzed into simple CHOs, they contain 3,4,5, and 6 carbons. (fructose, glucose, galactose)

Disaccharides-combinations of two monosaccharides (Maltose- glucose + glucose) (sucrose-glucose +fructose) (lactose- glucose +galactose)

Oligosaccharides- contain 3-6 monosaccharides

Polysaccharides- contain more than 6 monosaccharides

Front 26

Describe the importance of ribose in the Penthouse Powerhouse of Carbohydrate land and the HMP shunt (page 14)

Back 26

Ribose is an important component of nucleotides (like ATP) DNA and RNA; It is also part of NADH, FAD, and the CoA of acetyl CoA; ribose can be converted to glyceraldehyde 3-phosphate

Front 27

List 3 important functions of carbohydrates in the body

Back 27

Used for storage and generation of energy

Important structural components, both intra- and extracellular (glycolipids)

May be transformed into other, totally different kinds of molecules, like amino acids, lipids, and nucleic acids

When CHO attach to proteins and lipids, they form glycolipids and glycoproteins

Front 28

Name the enzymes required to breakdown glycogen into the form of glucose that can be used by the body, and identify where each is located

Back 28

Phosphorylase- liver and muscle

Salivary and Pancreatic Amylase- GI tract

Lysosomal alpha-glucosidase – all cells throughout the body

Front 29

Name the product of phophorylase reaction of glycogen breakdown

Back 29

Glucose-1-P

Front 30

Name the product of the amylase reaction of glycogen breakdown

Back 30

Maltose to maltase…which can then be broken down later into glucose

Front 31

Describe the function of insulin in the body

Back 31

Insulin is an anabolic hormone that signals the fed state, it reacts to feeding by clearing the blood of glucose, storing fuel, and promoting glycogen, fatty acid, and protein synthesis. It stimulates glycolysis and inhibits gluconeogenesis, facilitates entry of glucose into muscle and fat cells -> decreasing blood glucose

Front 32

Describe the function of epinephrine and glucagon, and identify where each is located

Back 32

Epinephrine-more effective in muscle

Glucagon- more effective in liver

They are hormones that promote glycogen breakdown, acting opposite to insulin; restore blood glucose levels by enhancing glycogen breakdown, decreasing glycogen synthesis, decreasing glycolysis and fatty acid synthesis and stimulating gluconeogenesis

Front 33

Describe the function of glucuronate, a product of carbohydrateland

Back 33

It can join with drugs, thereby inactivating them and facilitating their excretion. Plays important role in conjugation and excretion of bilirubin

Front 34

List 7 functions of lipids in the body (pg 17)

Back 34

1. Provide fuel- fatty acids, upon breakdown, form acetyl CoA, NADH, and FADH; stored as triglycerides
2. Compose cell membranes
3. Steroid hormones- side chains attach to the C17 carbon
Sex hormones- estrogen, progesterone, testosterone
Glucocorticoids- cortisol, cause a rise in serum glucose levels
Mineralocoricoids- aldosterone, retains sodium in body
4. Bile Acids- Part polar and nonpolar which facilitates their functioning as detergents, which bind to lipids and surrounding polar medium; emulsify fat in the gut
5. Prostoglandins- have diverse hormone like functions
6. Fat Soluble Vitamins – A, D, E, K
7.Lipids can combine with CHO or proteins to create glycolipids and lipoproteins

Front 35

Describe the difference between saturated and unsaturated fatty acids

Back 35

Saturated – contain only single bonds

Unsaturated – those that contain double bonds between some carbon atoms

Front 36

List the amount of energy provided by lipids, carbohydrates, and proteins, respectively

Back 36

Lipids 9 kcal/g

CHO 4 kcal/g

Proteins 4 kcal/g

Front 37

Describe the role of lipids when serum glucose is low

Back 37

Breakdown to triglycerides, the glycerol part of which can be used to produce more glucose

Front 38

Describe insulin's role in lipid metabolism

Back 38

Insulin inhibits lipid breakdown by a number of mechanisms and increases synthesis of glycogen, fatty acids, triglycerides, and proteins; reducing the level of cyclic AMP, promotes the transport of glucose into cells which can be converted and stored as triglycerides

Front 39

Define Essential Fatty Acid

Back 39

Required in the diet, as we cannot synthesize their double bonds, ex, Linoleate and linolenate

Front 40

Define Ketone:

Back 40

Produced in the course of breakdown of fatty acids

Front 41

Define Hydroxylation:

Back 41

Used to detoxify certain drugs; an oxidoreductase that facilitates couples oxidation of two donors with incorporation of oxygen into one of the donors, oxidation of the other donor and formation of water

Front 42

List the organs that can utilize ketones as fuel

Back 42

Brain during starvation

Cardiac Muscle

Front 43

Describe the disease state that elevated ketones in the blood may indicate

Back 43

Diabetes mellitus (type I)

Front 44

Name the form in which lipids are stored

Back 44

Triglycerides, they can be reverted to fatty acids and glycerol to be used as fuel

Front 45

List the function of prostoglandins

Back 45

Fatty acids contain 20 carbons arranged as a 5 carbon ring with 2 legs

Smooth muscle contraction- blood pressure, blood flow, degree of bronchial constriction and uterine contraction

Platelet aggregation

Inflammatory response- act as chemotactic agents, attracting leukocytes to the site of inflammation

Appear to increase pain and fever, induce sleep or wakefulness

Front 46

Describe the chemical structure that differentiates glycerol (used in the storage of fatty acids) from serine (used in the storage of sphingolipids)

Back 46

Glycerol has an –OH group in its middle carbon and an –OH group on the first carbon

Serine has an –NH2 on the middle carbon and a –COOH group on the first carbon

Front 47

List the structure and function of Ceremide:

Back 47

Are found in high concentrations within the cell membranes of cells. Can act as signaling molecule regulating the differentiation, proliferation, programmed cell death (apoptosis)

See page 20-21

Front 48

Structure and function of Sphyingomyelins:

Back 48

Are found in cell membranes and especially in the myelin sheaths that surround nerve axons

= ceramide plus a phosphorylcholine group

Front 49

Function and structure of Cerebrosides:

Back 49

Are found in myelin sheaths of nerves, in nervous tissues both grey and white matter of the brain and are major constituents of oligodendrocytes of the CNS

=a ceremide plus glucose or galactose

Front 50

Structure and function of Ganglioside:

Back 50

Can be found on the surface of oligosaccharides and provide cells with distinguishing surface markers that can serve in cellular recognition and cell to cell communication

= a ceremide plus an oligosaccharide and sialic acid

Front 51

List the biological functions of cholesterol:

Back 51

Give rise to fat soluble vitamins and coenzyme Q (used in e- transport)

LDL needed in the body. It occurs naturally in the body and is essential for bodily functions vital for life. LDL is also vital because it transports essential fatty acids into cells.

Cholesterol necessary for lipid bi-layer of cell
membranes. Over 90% of cholesterol is found in the body cells. If there is not enough cholesterol in the cell membrane, the walls lose their rigidity and expand outward, due to the inner pressure of the cell, leading to possible cell damage, or lysis.

Cholesterol is essential for life. Over 90% of cholesterol found in the body cells, where it give integrity to the cell structure and regulates the two way flow of nutrients and waste products.

Front 52

Organ System and Pathway Lipid Biosynthesis:

Back 52

Cell membranes (everywhere)

Front 53

Organ system and pathway lipid degradation:

Back 53

Cell membranes (everywhere)

Front 54

Organ system and pathway Lipid Storage:

Back 54

Fat cells

Front 55

Organ system and pathway Sphingolipids:

Back 55

Nervous system

Front 56

Organ system and pathway Cholesterol Production:

Back 56

Liver

Front 57

Organ system and pathway Bile acid production:

Back 57

Liver

Front 58

Organ system and pathway estrogen production:

Back 58

Ovaries

Front 59

Organ system and pathway androgen production:

Back 59

Testicles in men and adrenal cortex in women

Front 60

Organ system and pathway progesterone production:

Back 60

Ovaries, corpus luteum

Front 61

Organ system and pathway testosterone production:

Back 61

Testicles in men, adrenal cortex in women

Front 62

Organ system and pathway mineralocorticoid production:

Back 62

Adrenal cortex

Front 63

Organ system and pathway glucocorticoid production:

Back 63

Adrenal cortex

Front 64

Organ system and pathway Fatty acid production:

Back 64

Dietary triglycerides, esterified cholesterol, and phospholipids- broken down in the intestine through pancreatic lipase (d.tri -> free FA) cholesterol ester hydrolase (est chol -> unest chol) and phospholipase A2 (phospholipids-> lysophospolipids c only 1 FA group) which are absorbed

Front 65

Describe the areas of biochemistry land connected to lipid land and the relationship of each

Back 65

(Pg 23) Glycerol forms the backbone of the triglycerides, acetyl CoA forms fatty acids. Triglycerides can break down to glycerol and acetyl CoA, which is important fuel

Fatty Acids cannot form glucose, but the energy they release from the breakdown can be used to drive gluconeogenesis

AA Midway- Certain Aas, called ketogenic, can be converted into ketones, which can be used for energy or further synthesis

CHOland-formation of glycolipids

Front 66

Draw the basic structure of an amino acid:

Back 66

R
|
H2N - C - COOH
|
H

Front 67

Define Essential Amino Acid:

Back 67

Required in the diet, the body does not synthesize enough

Front 68

Define Protein:

Back 68

Very long chains of amino acids with different functions that depend not only on their specific amino acids but the overall shape of the sequence

Front 69

Define Globular Protein:

Back 69

Globe shaped, greatly folded and compact chains, ex. Albumin, hemoglobin, most enzymes

Front 70

Define Fibrous Protein:

Back 70

Contain straighter chains. Ex. Collagen, elastin, fibrogen

Front 71

Define Positive Feedback:

Back 71

Reduce the efficiency of particular enzymes that act at earlier reaction phases
Speed up if your driving too fast

Front 72

Define Negative feedback

Back 72

Increase the efficiency of particular enzymes that act at earlier reaction phases, used primarily throughout the body: ie. Endocrine system

Speed up if you are too slow, and slow down if you are too fast

Front 73

List the 10 essential amino acids

Back 73

Tryptophan Histidine Argenine Threonine (THAT)
Lysine Isoleucine Leucine (LIL)
Methionine Phenyalanine Valine (MPV)

Front 74

Describe Main Functions of Amino Acids

Back 74

Fuel- AAs are glucogenic (can convert to glucose) or ketogenic (convert to acetyl CoA)

Conversion to other molecules

Front 75

List the functions of Proteins

Back 75

Transport- other molecules

Storage

Motion- Proteins slide along one another and provide motion in muscles cilia, flagella, and microtubules

Structure: Collagen (structural framework) Elastin (stretchable support) Keratin (tough, nails and hair)

Control of gene expression- select proteins act on DNA to control the expression of genes

Growth substances- May promote growth and regeneration of tissues in the embryo and adult

Immune mechanisms- antibodies

Clotting mechanisms – Fibrinogen and thrombin

Cell membranes- Control passage and/or action of chemicals

Hormones

Enzymes- alter rates of chemical reactions

Front 76

Describe the determining factor of a functioning protein

Back 76

Frequently determined by the attachment of a non-polypeptide group.

AA specific sequence = primary structure and overall shape is the secondary tertiary or quaternary structure

Front 77

Describe the function of the urea restroom in the AA midway

Back 77

Excess AA must loose the NH2 group become other molecules. The NH2 group is excreted as urea.

Front 78

List the organ system where the following activities, related to amino acids and proteins occur:

Back 78

Urea Excretion: Urine and Sweat

Thyroxine: Thyroid gland

Norepinephrine production: Cells in sympathetic nervous system

Dopamine production: Neuronal Cells

Melanin production: Cells of the skin, and two areas of the brain, substantia nigra and locus coerdeus

Breakdown of ingested proteins: GI Tract by digestive proteins

Front 79

Describe the areas of Biochemland connected to the AA midway and the relation to each:

Back 79

Ketogenic and glucogenic AAs can convert to main powerhouse molecules. Nonessential AAs can be produced directly or indirectly. AAs can combine with CHO land to form amino sugars and glycoprotiens, and combine with lipids from lipidland to form lipoproteins. In the restroom AAs are stripped of ammonia and excreted as urea. The AA midway connects with the DNA funhouse to the formation of purines and pyrimidines.

Front 80

L-Dopa

Back 80

Precursor of dopamine

Front 81

Carbidopa:

Back 81

Inhibits dopa decarboxylase, does not cross the blood brain barrier

Front 82

Dopamine:

Back 82

Inhibits prolactin synthesis, too much prolactin may lead to a tumor

Front 83

Organ primarily responsible for the excretion of excess cholesterol

Back 83

Liver

Front 84

Describe the function of lipoproteins:

Back 84

Transport triglycerides ad cholesterol throughout the bloodstream, solubilize lipids internally through their non-polar groups and simultaneously be soluble in the bloodstream through their soluble end.

Front 85

Describe how Chylomicrons are processed in the body

Back 85

The main component, triglycerides are stored in fat cells. Fatty acids are used as energy sources, mostly in muscle cells. The triglycerides are dropped off largely in fat, and skeletal & heart muscle cells. A lipoprotein lipase releases fatty acid from the triglycerides. The remaining cholesterol particles go to the liver.

Front 86

Describe how VLDL are processed in the body:

Back 86

Are released by the liver and are rich in triglycerides and cholesterol. Like chyclomicrons they drop off their triglycerides in fat and muscle cells, The rest become rich LDL particles.

Front 87

Describe how IDL are processed in the body:

Back 87

Intermediate stage

Front 88

Describe how LDL are processed in the body:

Back 88

Distributes the cholesterol, widely to hepatic and non hepatic cells throughout the body

Front 89

Describe how HDL are processed in the body:

Back 89

Carries unwanted, excess cholesterol, partly from cell breakdown, back to the liver where the cholesterol might end up being excreted.

Front 90

Describe how LCAT is processed in the body:

Back 90

Associated with HDL and reesterfies free cholesterol

Front 91

List two base purines:

Back 91

Adenine

Guanine

Front 92

List three base pyrimidines:

Back 92

Cytosine

Uracil

Thymine

Front 93

Describe the importance of purines and pyrimidines:

Back 93

They are the building blocks of DNA and RNA

Front 94

Outline the chemical steps needed to go from purine/pyrimidine to DNA/RNA

Back 94

Purine/Pyrimidine + sugar moity (ribose or deoxyribose = mucleoside)

Nucleoside + phosphate moity = nucleoside

Nucleotide in sequence = DNA or RNA

Front 95

List the pairs that cross-connect the double strands DNA

Back 95

Adenine and Thymine

Guanine and Cytosine

Front 96

List the events that occur in the formation of DNA:

Back 96

Replication-reproduction of DNA

Transcription- formation of RNA and DNA

Translation – formation of protein on the messenger RNA molecule

Front 97

Explain steps of Replication:

Back 97

Helicase unwinds the DNA double helix. Topoisomerase reduces the supercoiling tat occurs during the unwinding process. Primase synthesizes a short strand of RNA, which acts as a primer in initiating DNA polymerization.

DNA polymerase sequentially polymerizes nucleotides to form a new DNA strand. DNA polymerases also have exonuclease properties- the ability to hydrolyze and remove improperly paired terminal nucleotides

DNAligase connects newly formed (okasaki) fragments of DNA with one another to form a single chain

Endonucleases can hydrolyze connections between those nucleotides that lie within the central area of the nucleotide chain

Front 98

Explain the steps of Transcription:

Back 98

RNA polymerase sequentially polymerizes nucleotides on the DNA template to form an RNA copy of one of the DNA strands

Promoters are regions on DNA that signal the RNA polymerase where to begin polymerization. DNA also contains stop signs to signal where the RNA transcription should stop. The resulting RNA molecule may subsequently be modified by adding or subtracting from the RNA chain. This forms the 3 types of RNA.

Front 99

Describe the steps of Translation:

Back 99

mRNA carries the genetic code in the form of purines and pyrimidine base triplets, called codons, Each codon corresponds to a specific amino acid on a transfer RNA molecule. An anticodon is the recognition site on a tRNA molecule tha recognizes a specific mRNA codon, enabling the tRNA with its attached aminoacid, to line up properly on the mRNA. There are 61 codons and 20 Aas. There are three terminal codons that specify stop signal to protein synthesis. Amino acyl-tRNA synthetase is an enzyme that attaches Aas to their corresponding tRNA.

Front 100

Understand how the direction 5’ to 3’ formation is important in making new DNA/RNA

Back 100

Antiparallel manner, reads 3 to 5 and writes 5 to 3, base pairs are situated at the central core of the helix so the base pairs match.

Front 101

Define mRNA:

Back 101

Carries the primary message if the specific proteins to be synthesized on the ribsomes

Front 102

Define tRNA:

Back 102

Transfers individual specific amino acids to be linked up on mRNA molecules

Front 103

Define Okazaki Fragments:

Back 103

Short DNA strands formed during replication of the lagging strand, they are later joined by DNA ligase

Front 104

Define Codon:

Back 104

mRNA carries the genetic code in the form of triplets of purines and pyrimidines

Front 105

Define Anticodon

Back 105

The recognition site on a tRNA molecule that recognizes a specific mRNA codon, enabling the tRNA

Front 106

List the areas of biochemistryland that are connected to the DNA Funhouse, and briefly describe the relationship to each:

Back 106

Ribose 5-P is used in forming purines and pyrimidines. AAs are used to form purines and pyrimidines, alanine is a breakdown product of cytosine and uracil. It connects with the Kreb’s cycle via the urea restroom as aspartate and glutamate 3-aminosobutyrate, a product of thymine degradation, may connect to succinyl CoA.

Front 107

List the important molecules that are made from pyrrol rings (petals) in Porphy’s Heme Land

Back 107

Heme, vitamin B12, cytochromes, catalase, peroidase, chlorophyll (plants)

Front 108

Outline the chemical steps needed to go from protoporphyrin to hemoglobin

Back 108

Protoporphyrin + iron = heme

Heme + globin protein = hemoglobin

Front 109

Define the difference between hemoglobin and myoglobin

Back 109

Hemoglobin – four polypeptide chains each with their own heme group, carries O2 in blood

Myoglobin – one polypeptide chain, carries O2 in muscle

Front 110

Outline the steps in the breakdown of hemoglobin in the body:

Back 110

Bilirubin and its derivatives are the broken down products of hemoglobin, which are components of bile. When red blood cells are broken down the heme ring breaks and Fe++ is released, forming biliverdin, an open chain molecule with no iron. Biliverdin is changed to unconjugated bilirubin by reduction of its central carbon. The molecules then move into circulation but are water insoluble and must be carried to the liver by albumin. The liver cells take up the unconjugated bilirubin and transform it into conjugated bilrubin by conjugating with glucuronate, and is now soluble in water. This is released into the biliary duct and then to the small intestines. There the conjugated bilirubin is transformed into urobilinogen. Some is excreted and some is reabsorbed. It is water soluble and may be released in the urine. The dark color of stool is due to the converstion of urobilinogen (colorless) to stercobilinogen (colorless) to stercobilin (brown) in the intestines.

Front 111

List the areas of the body where the following chemical mechanisms take place:

Back 111

Heme Production: All over, especially bone marrow

Bilirubin Metabolism: Liver, intestine, and blood stream

B-12 Production: Microorganisms

Storage: Liver

Front 112

List the components stocked in the infirmary:

Back 112

Vitamins, minerals, drugs, and equipment for lab tests

Front 113

List the water soluble vitamins:

Back 113

B1 (thiamine)

B2 (riboflavin)

B6 (pyridoxine, pyridoxal, & pyridoxamine)

B12 (cobalamin)

C (ascorbic acid)

Folacin (folic acid)

Biotin

Miacin (nicotinic acid)

Pantothenate (pantothenic acid)

Front 114

List the fat soluble vitamins:

Back 114

A (retinal)

D (Calciferol)

E (tocopherol)

K

Front 115

Define the function of the intrinsic factor:

Back 115

Facilitates transport of B12 from the gut to the general circulation, a glycoprotein produced in the stomach

Front 116

Describe the function of Vitamin C:

Back 116

Conservation of proline to collagen hydroxyproline, acts as an antioxidant that protects a variety of molecules from oxidation, facilitates the absorption of iron in the intestines by reducing it to a more absorbable Fe++ form, plays a role in the synthesis of epinephrine and norepinephrine

Front 117

Describe the function of Vitamin A:

Back 117

Retinal is a part of the rod photoreceptor pigment rhodopsin, and cone photoreceptor pigment iodopsin. When the light strikes the retinal part of the molecule, the “cis” form changes to trans-retinal, which initiates the chain of neuronal impulses. Trans-retinal changes back to the cis form, helps maintain skin and mucosal surfaces and helps growing bone. May effect alterations in gene expression.

Front 118

Describe the function of Vitamin D:

Back 118

Produced in the body in response to sunlight, helps to raise the blood levels of calcium and phosphorus, stimulates Ca and P absorption in the GI tract, promotes transfer of Ca and P from bone to bone, promotes Ca retention by the kidney. As a hormone, it acts by entering the cell nucleus and interacting with DNA to regulate protein synthesis via a vitamin D receptor.

Front 119

Describe the function of Vitamin K:

Back 119

Produced by plants and bacteria in the intestine, necessary for the production of prothrombin and other clotting factors in the liver, acts as a coenzyme in the carboxylation of several clotting factor proteins.

Front 120

Describe the importance of Folate:

Back 120

Precursor of THF, important in rapidly dividing cells in bone marrow

Front 121

Define the importance of Niacin:

Back 121

Part of NADH and NADPH

Front 122

Define the importance of B6:

Back 122

A coenzyme that prefers AA metabolism, it is the prosthetic group for all transaminases

Front 123

Define the importance of Pantothenic Acid:

Back 123

Part of the CoA molecule, part of the acetyl carrier protein of fatty acid biosynthesis

Front 124

List the hormones that are protein and polypeptide derivatives:

Back 124

Protein:

Growth Hormone
Prolactin
Leptin


Polypeptide:

Adrenocorticotrophic Hormone (ACTH)
Antidiuretic Hormone (ADH or Vasopressin)
Oxytocin
Parathyroid Hormone (PTH)
Insulin
Glucagon
Gastrin

Front 125

List the hormones that are AA derivatives:

Back 125

Melatonin

T4

T3

Epinephrine

Front 126

List the hormones that are cholesterol (steroids) derivatives:

Back 126

Glucocorticoids

Mineralocorticoids

Estrogen

Progesterone

Testosterone

Front 127

Explain Glucose 6-phosphatase deficiency:

Back 127

Glycogen Storage Disease, there is a deficiency at this step in the formation of glucose in the liver. This instead forms other things:

Liver swells with glycogen

There is excess uric acid which leads to stones in the urinary tract

Excess triglycerides are broken down to release fatty acids, resulting in fatty deposits

Excess pyruvates and lactate result in a serum acidosis

Diagnosed through liver biopsy

Front 128

Explain lactase deficiency:

Back 128

Deficiency of intestinal microvilli, results in poor digestion of lactose, bloating, cramps, and diarrhea. May be hereditary or developed from an intestinal disease. Diagnosed through a small bowel biopsy or lactose tolerance test, testing blood glucose or hydrogen breath test where hydrogen in breath increases when intestinal bacteria act on undigested lactose.

Treated with lactose restriction

Front 129

Explain Cyanide Poisoning:

Back 129

Interferes with electron transport in the Kreb’s Cycle. Cyanide binds to the Fe++ of cytochrome oxidase and prevents oxygen from combining with cytochrome oxidase.

It also binds with Iron and methemiglobin, this provides treatment with sodium nitrate. Nitrate converts hemoglobin to methemoglobin which remove cyanide from cytochrome oxidase, Then one takes sodium thiosulfate to react with cyanide to form benign thiocynate which is excreted in the urine.

Another possible treatment is large amount of glucose with insulin to stimulate glycolisis.

Front 130

Explain Carbon Monoxide Poisoning:

Back 130

Combines with the heme of both cytochrome oxidase and hemoglobin.

Treated with hyperbaric oxygen, which competes with carbon monoxide for the hemoglobin.

Front 131

Explain Arsenic Poisoning:

Back 131

In its arsenate form prevents the transformation of glyceraldehyde 3-P to 3-P glycerate.

Arsenate is similar to phosphate and can sub for it in oxidative phosphorylation and attach to glyceraldehyde 3-P. The result is the same as normal butdoes not produce ATP normally.

Front 132

Explain Alcohol Intake:

Back 132

May result in hypoglycemia because alcohol metabolism produces NADH, an excess prevents lactate from being transformed to glucose and may lead to lactate accumulation.

Elevated NADH also inhibits the conversion of malate to oxaloacetate.

Front 133

Explain Diabetic Ketosis: With Insulin

Back 133

Clears blood of glucose (into cells)= glycogen storage

Decreases gluconeogenisis

Forms malonyl CoA which helps in using Acytl CoA and inhibits FA oxidation

Front 134

Explain Diabetic Ketosis: Without Insulin

Back 134

No glucose into cells = not able to be used, so triglycerides have to break down to provide acytl CoA for Krebs Cycle, but because of the gluconeogenisis and lack of oxoloacetate in the Krebs Cycle a lot of the Acytl CoA cannot get in and will accumulate to form ketones

Increase to gluconeogenisis. The glucose for this comes fro the oxoloacetate from the Kreb’s Cycle, therefore, it is no longer able to be used by the Kreb’s Cycle to combine with Acetyl CoA.

Deficit in Malonyl CoA leads to Acytl CoA accumulation, therefore even more that cannot be used due to the lack of oxoloacetate. Increase in FA breakdown which makes ketones. Some FA travel to liver and liver overwhelmed therefore get a fatty liver and increase in blood lipids

Front 135

Explain Kwashiorkor:

Back 135

May be a fatty liver, patient ingests sufficient calories but have poor protein intake.

Proteins are needed so the liver forms and releases lipoproteins, which carry lipids. Lipids accumulate in the liver, this leads to swelling and ascites.

Front 136

Explain Pancreatitis:

Back 136

Pancreatic lipase releases fatty acids from glycerides. This is usually kept in inactive form in the pancreatic cell. Pancreatitis activates these enzymes and causes damage.
Pancreatic lipase becomes prematurely active while still in pancreatic cell.

Front 137

Explain Nerve Gas:

Back 137

Inhibits acetyl cholinesterase, important in the degree of acetylcholine to choline. This causes paralysis through inhibiting AchE between peripheral nerves and muscle, then respiratory paralysis.

Front 138

Explain Cytochrome:

Back 138

Functions in hydroxylation, important in combination of O2 with cholesterol and its derivatives, where hydroxyl groups area added at key steps. It also detoxifies drugs in the liver. Has also been implicated in inducing cancer by converting potential carcinogens in more active forms.

Pg 450

Front 139

Explain Gallstones:

Back 139

Composed of cholesterol, stones form when cholesterol/bile salt- phospholipid ratio increases. Chenodeoxycholate is used for gall therapy, provides extra recirculating source of bile acids and inhibits the rate-limiting step in cholesterol biosynthesis.

Front 140

Explain Phenylketonuria:

Back 140

The defect may not be in the enzyme, bit in the ability to regenerate tetrahydrobiopterin. This is necessary for this reaction. There is buildup and excretion of phenylpyruvate in the urine, causing a mousy odor. Results in mental retardation. Diagnosis is made by urine testing or serum testing. Treatment is diet low in phenylalanine.

Front 141

Explain Parkinson’s Disease:

Back 141

Deficiency of dopamine in the brain stem, mainly the midbrain. There is a marked loss of substantia nigra cells, which leads to slowness, stiffness, and tremors. Treated with L-DOPA, the precursor of dopamine because it can cross the blood brain barrier. Carbidopa is paired with L-DOPA, it doesn’t cross the blood brain barrier.

Front 142

Explain Histamine Effect:

Back 142

Allergy and shock, released under the prescence of certain drugs, tissue trauma and antigen-antibody allergic interactions. Causes arteriole relaxation. It excites smooth muscle, this may lead to bronchospasm. Stims sensory nerve endings, leading to itching and pain. Also stims gastric secretion.

Front 143

Explain Chromolyn effect:

Back 143

Inhibits release of histamine in mast cells, used in treatment of asthma.

Front 144

Explain Cimetidine Effect:

Back 144

Drug that resembles histamine in structure. Compete with histamine for receptors in the stomach, useful for reducing gastric acid secretion in the treatment of peptic ulcers.

Front 145

Explain Scurvy:

Back 145

There is a defective collagen formation, bruises easily and has decaying gums.

Front 146

Explain Beri-beri:

Back 146

Deficiency in vitamin B1 from eating a diet of refined rice or with excess cooking of food. Cardiac and neurological complication, such as palpitations, edema, weakness and pins and needles and pain in the legs.

Front 147

Explain Wernicke-korsakoff syndrome:

Back 147

Due to alcohol and B1 deficiency, a direct inhibition of absorption in the gut, or may be hereditary. Confabulation (fabrication of stories), memory loss and other me neurological problems, such as muscle weakness, nystagmus. May receive thiamine treatments as a part of alcohol therapy.

Front 148

Explain Pernicious Anemia:

Back 148

Deficiency comes from diseases of the intestine that impede absorption, tapeworms, or a deficiency of gastric intrinsic factor which may be from gastrectomy or an autoimmune disease. Macrocytic anemia, hypersegmented leukocytes and neurosensory deficits. Diagnosed with a serum level test or a positive Schilling test, where radioactive B12 is ingested. Treatment is injection of B12.

Front 149

Explain Folic Acid Deficiency:

Back 149

Similar to B12, anemia, folate must be replaced in the diet. Diagnosed with a serum test.

Front 150

Explain Pellagra:

Back 150

Most likely a deficiency in niacin and tryptophan, from a diet in corn. Diarrhea, dermatitis and dementia. Diagnosing is difficult but may be done by improvement in niacin development.

Front 151

Explain Rickets:

Back 151

Deficiency in Vitamin D causes deficiency in hypocalcemia and hypophosphatemia leading to bending with poor calcification of developing bone in children, impaired mineralization.

Front 152

Explain Myxedema:

Back 152

Deficiency of thyroxine in children results in a dwarf. In an adult, dry edematous skin, mental, and physical sluggishness, decreased tendon reflexes, lower metabolism, and a goiter. Due to low production by the thyroid gland from an autoimmune disease or low iodine intake.

Front 153

Explain Graves Disease:

Back 153

Excess thyroxine, goiter, exophthalmos and hyperactivity and high metabolism.

Front 154

Explain Cushings:

Back 154

High plasma cortisol levels, resulting in abnormal glucose metabolism (diabetes), moon face, back fat, abnormal protein breakdown, androgen secretion, ulcers, psychosis and decreased inflammatory response. May be due to an ACTH- secreting tumor.

Front 155

Explain Addison’s Disease:

Back 155

Cortisol insufficiency and sometimes low levels of aldosterone. Hypertension, low serum sodium, weakness and excess skin pigmentation. Secondary to autoimmune disease or infection.

Front 156

Explain Pheochromocytoma:

Back 156

Excess epinephrine from a tumor. Hypertension, cardiac palpitations and anxiety. Urinary VMA may be elevated.

Front 157

Explain Diabetes:

Back 157

Deficiency in insulin, hyperglycemia, glycosuria and sometimes ketoacidosis. High blood sugars result in osmotic fluid loss and coma.

Page 65

Front 158

Explain Gout:

Back 158

Elevation of uric acid in the blood and urine. Urate crystals precipitate joints (big toe) and urine. Hyperuremia from excess production of uric acid. Caused by metabolic defects, malignancies, renal disease, and alcohol.

Front 159

Explain Sickle Cell:

Back 159

Hereditary, abnormal hemoglobin is produced that leads to sickle-shaped RBCs, esp. under O2 deprivation. May clog small blood vessels. Diagnosed by blood smear or electrophoresis. There is a change in the beta chain.

Front 160

Explain Thallassemia:

Back 160

Genetic condition that causes anemia, the polypeptide chains are normal, but abnormal quantities are produced.

Front 161

Define Enantiomers:

Back 161

Sterioisomers that mirror each other

Front 162

Define Epimers:

Back 162

Diasteriomers that differ in conformation around one carbon

Front 163

Define Cis and Trans:

Back 163

Diasteriomers that result from configuration about a double bond.

Front 164

Define Hydrolases and list them:

Back 164

Catalyzes hydrolysis of a bond

Esterases

Lipases

Nucleosidases and – tidases

Peptidases

Phosphatases

Sulfactases

Front 165

Define Isomerases and list them:

Back 165

Catalyzes the rearrangement of Isomers

Epimerases

Certain Mutases

Racemases

Front 166

Define Ligases and list them:

Back 166

Enzymes that catalyzes the joining of 2 molecules

Carboxylases

Synthetases

Front 167

Define Oxidoreductases and list them:

Back 167

AN enzyme that catalyzes the transfer of electrons from one compound to another.

Dehydrogenases

Desaturases

Hydroxylases

Oxidases

Oxygenases

Reductases

Front 168

Define Transferase and list them:

Back 168

An enzyme that catalyzes the transfer of a functional group from one enzyme to another.

Kinases

Certain Mutases

Phosphorylases

Polymerases

Transaldolase and –ketolase

Transaminases

Front 169

unknown title.. Treatment of lipid disorders?

Back 169

Treatment of lipid disorders, intake, cholestyramine, micotinic acid, Hmg coA reductase medications