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187 Cards in this Set

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What percentage of total body water is made up of plasma?
7%
What percent of body water is considered interstitial fluid?
26%
What percentage of water is considered intracellular fluid?
67%
Is more fluid intra- or extracellular?
About twice as much body water is in intracellular fluid than extracellular (33% intracellular as opposed to 67% extracellular)
Define: Set point
The mean steady-state value maintained by a homeostatic system (about which there exists a range of values).
Define: Feedback control system
A system in which the regulatory signal depends upon the read "output" value.
Define: Negative feedback system
A feedback system whose regulatory signal operates to decrease the difference between the read "output" value and the desired value.
Define: Positive feedback system
A feedback system whose regulatory mechanism increases the effect of any perceived disturbance, ultimately driving the system to extremum.
Define: Feed-forward control system
Control mechanism has predictive quality. Regulation can only come from brain.
Define: Control theory
Theory of regulation of a system's reaction to disturbance
Define: Control system
System arranged in such a way that it can self-regulate (and/or regulate other systems)
What are the limitations of negative feedback?
Can correct for disturbances that affect the system, but not those that affect perception of system variables (in which case the "output" that is compared the set-point is not the actual output).
How does a physiological variable under positive control returned to its steady-state value after having been driven to an extremum?
After reaching extremum, negative feedback control restores the system to its initial set point.
Levels of Organization
oChemical
oCellular
oTissue
oOrgan
oOrgan Systems
oOrganism
Factors controlled by Homeostasis
1. Concentration of nutrients
2. Concentration of gases
3. Concentration of wastes
4. Regulation of pH
5. Concentration of water, ions
6. Blood volume and pressure
7. Temperature
Scientific Method
•Observation
•Hypothesis
•Experiment (control group and experimental group)
•Collecting data
•Conclusions
The Physiology of Science- Based on Hypothesis
•Hypothesis-based science involves:
•Observations, questions, hypotheses as tentative answers to questions
•Deductions leading to predictions, and then tests of predictions to see if a hypothesis is falsifiable
What is a hypothesis?
•A hypothesis is a tentative or educated guess at an answer to a problem or question that is being asked.
•A good hypothesis makes predictions that can be tested.
•Part of the process of hypothesis-based science uses deductive reasoning, which flows from a general premise to a specific premise.
•The important aspect of this process is that the deduction can be tested.
Homeostasis
process by which a stable internal environment within an organism is maintained
Homeostasis: Intracellular vs Extracellular
a
Receptor
a
Effector
a
What are some important homeostatic mechanisms?
The maintenance of a water and solute balance, osmoregulation, the removal of metabolic waste products, excretion, the regulation of blood glucose levels, and the maintenance of a constant internal body temperature, thermoregulation
What are the primary homeostatic organs in humans?
The kidneys, liver, the large intestine, and the skin
What are the three processes that regulate salt and water balance in blood?
Filtration, secretion, and reabsorption
How does reabsorption work?
Essential substances such as glucose, salts, and amino acids and water are reabsorbed from the filtrate and returned to the blood
What does Na+ reabsorption do?
It increases water reabsorption, leading to a rise in blood volume, and hence a rise in blood pressure
What does the high glucose concentration in a diabetic do to the nephron’s active transport system?
It overwhelms it, leading to the excretion of glucose in the urine
What does the liver do?
It helps regulate blood glucose levels and produces urea
What happens to glucose-rich blood in the liver?
It is processed, which converts excess glucose to glycogen for storage
What happens if the blood has a low glucose concentration?
The liver will convert glycogen into glucose and release it into the blood
How does the liver synthesize glucose from non-carbohydrate precursors?
Via the process of gluconeogenesis
What else is the liver responsible for processing?
Nitrogenous wastes
What happens to excess amino acids?
They are absorbed in the small intestine and transported to the liver via the hepatic portal vein
They undergo a process called deamination
What is deamination?
It is when the amino group is removed from the amino acid and converted into ammonia, a highly toxic compound
What happens to the ammonia?
2 POSSIBILITIES....
1. Excreted in the urine
OR
2. The liver combines the ammonia with carbon dioxide to form urea, a relatively nontoxic compound
What happens to the urea?
1. It is released into the blood and eventually excreted by the kidneys
What else is the liver responsible for?
Detoxification of toxins, storage of iron and vitamin B12, destruction of old erythrocytes, synthesis of bile, synthesis of various blood proteins, defense against various antigens, beta-oxidation of fatty acids to ketones, and interconversion of carbohydrates, fats, and amino acids
What does the large intestine do?
It absorbs water and sodium not previously absorbed in the small intestine and are
An excretory organ for excess salts
factors can affect the rate of chemical reactions
1. Temperature
2. Concentration
3. Size
4. pH
5.Biological catalyst (enzymes)
Give three properties of water and explain how each function works in the body.
a
What are the three parts of every amino acid molecule?
a
What are the three parts to every nucleotide?
a
Compare and contrast DNA and RNA(include functions, structure, shape, where they are found in the cell)
a
Adenosine Triphosphate
RNA nucleotide containing adenine and two additional phosphate groups
What is cellular metabolism?
It is the sum of all chemical reactions that take place in the cell
Anabolic Reactions
biosynthesis of complex organic compounds from simpler molecules; requires energy
Catabolic Reactions
releases energy; break down of complex organic compounds into smaller molecules
What are heterotrophic organisms?
They obtain their energy catabolically, via the breakdown of organic nutrients that must be ingested
What is the net reaction of glucose catabolism?
C6H12O6 + 6O2+ 6CO2 + 6H20 + Energy
Where is the energy of ATP stored?
In the covalent bonds attaching the phosphate groups
What is ATP composed of?
It has the nitrogenous base adenine, the sugar ribose, and three weakly linked phosphate groups
What is a second mechanism by which the cell stores chemical energy?
It stores energy in the form of high potential electrons
What happens during glucose oxidation?
*Hydrogen atoms are removed
*They are accepted by NAD+, FAD, and NADP+
What do NAD+, FAD, and NADP+
do?
transport the high-energy electrons of the hydrogen atoms to a series of carrier molecules on the inner mitochondrial membrane
So, what do these coenzymes ultimately do?
temporarily store and release energy in the form of electrons through their successive oxidations and reductions
What is glycolysis?
series of reactions that lead to the oxidative breakdown of glucose into two molecules of pyruvate
Products of glycolysis (per 1 molecule of glucose)
2 pyruvate
2 net ATP
2 NAD+
2NADH
2H
2H20
type of phosphorylation in glycolysis?
substrate level phosphorylation
What is fermentation?
This is the reduction of pyruvate into ethanol or lactic acid.
Alcoholic fermentation
The pyruvate is decarboxylated to become acetaldehyde. The acetaldehyde is reduced by the NADH generated in glycolysis to yield ethanol. It produces NAD+ so that glycolysis can continue
Lactic Acid fermentation
The pyruvate is reduced to lactic acid. Then regeneration of NAD+ . The pH goes down in the blood, which causes muscle fatigue. The lack acid is oxidized back to pyruvate and the cell enters cellular respiration when oxygen is restored
How much energy does cellular respiration yield?
36-38 ATP
What is the role of oxygen in the electron transport chain?
It acts as the final acceptor of electrons that are passed from carrier to carrier during the electron transport chain (the final stage of glucose oxidation)

-catalyzed by Reaction-specific enzymes
What happens during pyruvate decarboxylation?
The pyruvate formed during glycolysis is transported from the cytoplasm into the mitochondrial matrix where it is decarboxylated (loses its CO2)
When does the citric acid cycle begin?
\when the two-carbon acetyl group from acetyl CoA combines with oxaloacetate. It forms the six-carbon citrate

2 CO2 are released, and oxaloacetate is regenerated for use in another turn of the cycle
What type of phosphorylation occurs in the citric acid cycle?
Substrate level phosphorylation
What happens to NAD+ and FAD during the CA cycle?
Electrons are transferred to them, making NADH and FADH2
Where do these coenzymes transport the electrons to?
to the electron transport chain where more ATP is produced Through oxidative phosphorylation
Per molecule of glucose, how many pyruvates are decarboxylated and channeled into the citric acid cycle?
2 Pyruvates
net products of the citric acid cycle (per glucose molecule)?
6 NADH
4 CO2
4 H+
2 FADH2
2 ATP
2 CoA
What is the electron transport chain?
It is a complex carrier mechanism located on the inside of the inner mitochondrial membrane
What happens during oxidative phosphorylation?
ATP is produced when high energy potential electrons are transferred from NADH and FADH2 to oxygen by a series of carrier molecules located in the inner mitochondrial membrane
In the ETC, What happens as electrons are transferred from carrier to carrier?
Free energy is released; It is used to form ATP
In the ETC, What is FMN or flavin mononucleotide?
It is the first molecule of the ETC
In the ETC, What else does the O2 pick up besides electrons?
also picks up a pair of hydrogen ions from the surrounding medium; this forms H2O
In the ETC, What happens if there is no oxygen?
The ETC becomes backlogged with electrons.

NAD+ cannot be regenerated and glycolysis cannot continue unless lactic acid fermentation occurs.
What does cyanide or dinitrophenol do?
They stop ATP synthesis.

Cyanide blocks the transfer of electrons from cytochrome a3 to O2. Dinitrophenol uncouples the electron transport chain from the proton gradient established across the inner mitochondrial membrane
What are the three large protein complexes that electron carriers are classified as?
NADH dehydrogenase, the b-c1 complex, and cytochrome oxidase
An electron passing through the entire ETC supplies enough energy to generate how many ATP?
3 ATP
For each NADH--NADH delivers its electrons to NADH dehydrogenase complex, which produces how many ATP?
3 ATP
For each FADH2--FADH2 delivers its electrons to ubiquinone, which produces how many ATP?
2 ATP
What happens as NADH passes its electrons to the ETC?
Free hydrogen ions are released and accumulate in the mitochondrial matrix
What does the ETC do to these ions?
It pumps them out of the matrix, across the inner mitochondrial membrane, and into the intermembrane space at each of the three protein complexes
What does this continuous translocation of H+ create?
A positively charged acidic environment in the intermembrane space
What does the electrochemical gradient generate?
A proton-motive force (the force that drives the H+ back across the inner membrane and into the matrix)

To pass through the membrane which is impermeable to ions, the H+ must flow through specialized channels provided by enzyme complexes--called ATP synthases
What is the coupling of the oxidation of NADH with the phosphorylation of ADP called?
Oxidative phosphorylation
What happens when glucose supplies run low?
The body utilizes other energy sources--carbohydrates first, then fats, then proteins

These substances are first converted to either glucose or glucose intermediates, which can be then degraded in the glycolytic pathway and the TCA cycle
How does it work with carbohydrates?
Disaccharides are hydrolyzed into monosaccharides, most of which can be converted into glucose or glycolytic intermediates
What can glycogen in the liver be converted into?
glucose-6-phosphate, (a glycolytic intermediate)
In cell respiration--What can fats be converted into energy?
triglycerides (stored in adipose tissue) are hydrolyzed by lipases to fatty acids and glycerol, and are carried by the blood to other tissues for oxidation
What can glycerol be converted into?
G3P; glyceraldehide 3-phosphate (a glycolytic intermediate)
What must first happen for the fatty acid?
It must be activated in the cytoplasm. this process requires 2ATP.

Once activated, The fatty acid is transported into the mitochondrion and taken through a series of beta-oxidation cycles--which converts them into two-carbon fragments.

Then, they are converted into acetyl CoA & enter the Citric Acid Cycle
With each round of beta-oxidation of a saturated fatty acid, what is generated?
what is generated? 1 NADH and 1 FADH2
How do proteins get converted into ATP?
The body degrades amino acids only when there is not enough carbohydrate available.

Most undergo a transamination reaction
What happens to the protein in a transamination reaction?
It loses an amino group to form an alpha-keto acid
What happens to the carbon atoms of most amino acids?
Most are converted into acetyl-CoA, pyruvate, or one of the intermediates of the citric acid cycle
When you hear the use of coenzymes that act as reducers, what two coenzymes should you think of?
NADH
FADH2
By what process is ATP produced in glycolysis? Explain in detail how this process works.
The initial phosphorylation of glucose is required to destabilize the molecule for cleavage into two G3P.

Then, (for each G3P), 4 phosphate groups are transferred to ADP by substrate-level phosphorylation to make 4 ATP and 2 NADH are produced when the triose sugars are oxidized.
10. Which of the cellular respiration processes operate in the presence of oxygen. Which respiration process is termed anaerobic?
Only glycolysis may be anaerobic
How many times does the cycle turn for each glucose molecule?
2
Transfer of the amine group is called __________________.
transamination

the transamination reaction results in the exchange of an amine group on one acid with a ketone group on another acid. It is analogous to a double replacement reaction.

The most usual and major keto acid involved with transamination reactions is alpha-ketoglutaric acid, an intermediate in the citric acid cycle. A specific example is the transamination of alanine to make pyruvic acid and glutamic acid.
The resulting molecule then goes through _______________________ which completely removes the amine group.
oxidative deamination

During oxidative deamination, an amino acid is converted into the corresponding keto acid by the removal of the amine functional group as ammonia and the amine functional group is replaced by the ketone group. The ammonia eventually goes into the urea cycle.

Oxidative deamination occurs primarily on glutamic acid because glutamic acid was the end product of many transamination reactions.
Proteins used for ATP
Proteases break the peptide bonds of proteins back down to amino acids
Deaminases break the amino group off the amino acids, releasing ammonia. This toxic ammonia is converted to urea, and is excreted in urine.
The remainder of the amino acid (mostly of carbon, hydrogen, and oxygen), and can be rearranged in cells to enter cellular respiration either as pyruvate, as acetyl CoA, or directly into the Krebs cycle.
Result: Still ~32-38 or so ATPs, but from proteins, not glucose!
Fats used for ATP
Lipases break the glycerol head away from the fatty acids.
Glycerol is converted to an intermediate in glycolysis called "PGAL", and enters cellular respiration in the cytoplasm.
The fatty acid tails are converted to Acetyl CoA and enter the Krebs cycle in the mitochondria
Result: Still ~32-38 or so ATPs, but from fats, not glucose!
After Glutamic Acid undergoes oxidative deamination, it converts back to ________
the keto acid
kreb cycle products
-6 NADH's are generated (3 per Acetyl CoA that enters)
-2 FADH2 is generated (1 per Acetyl CoA that enters)
-2 ATP are generated (1 per Acetyl CoA that enters)
-4 CO2's are released (2 per Acetyl CoA that enters)
Describe the 2 steps of glycolysis--
The First Stage of Glycolysis---

•Glucose gets into the cell by facilitated diffusion
-•Glucose phosphorylated
-Glucose (6C) is broken down into 2 G3P;This requires two ATP's

The Second Stage of Glycolysis---

-•Molecules go through oxidation, production of ATP
-2 G3P (3C) are converted to 2 pyruvates-This creates 4 ATP's and 2 NADH's
The net ATP production of Glycolysis is 2 ATP's
Describe the intermediate step (between glycolysis and the citric acid cycle)
The Oxidation of Pyruvate to form Acetyl CoA for Entry Into the Krebs Cycle

•PA goes through oxidation, reduction, decarboxylation
•PA is now Acetic acid (2C)
•Coenzyme A attaches to Acetic acid> Acetyl CoA

2 NADH's are generated (1 per pyruvate)
2 CO2 are released (1 per pyruvate)
Describe the Kreb Cycle
•Acetyl CoA enters cycle and joins with oxaloacetic acid (4C)
•Citric Acid (6C) is formed > beginning molecule in cycle
•Citric acid goes through a series of oxidation, reduction, decarboxylation rxns to form oxaloacetic acid again.
•During this process, 1 ATP is formed
•Coenzymes NAD, FAD pick up hydrogens
Describe the Electron Transport Chain
• NAD and FAD drop off their hydrogens to the chain
• Hydrogens are split into electrons and protons
• Electrons are shuttled down/along the chain
• proton pumps are activated
• protons flow through special membrane channel that produces ATP
1.Substrate level phosporylation
no oxygen needed, occurs in glycolysis and kreb’s cycle.
What are the 3 functions of the Cell membrane?
1. To selectively impede molecules from passing in/out of the cell.

2. To detect chemical signals from cells

3. To anchor the cell to other cells and the extracellular matrix.
what are intrinsic and extrinsic proteins?
intrinsic - protein spans the membrane

extrinsic - protein is on one side or the other of the membrane, or partway through.
what 4 things are membranes permeable to?
-fat
-oxygen
-carbon dioxide
-steroids
what is the driving force for diffusion?
concentration gradient
What does "amphipathic" mean?
Possessing both hydrophilic and hydrophobic regions.
i.e. phospholipids!
What are the differences between integral, peripheral, and lipid-anchored proteins?
integral: embedded within bilayer, held in place by affinity of hydrophobic segments to the interior of the bilayer.
peripheral: more hydrophilic and located on membrane surface, linked noncovalently to polar head groups on lipids or to other hydrophilic protein regions.
lipid-anchored: hydrophilic as well, but covalently linked to lipid molecules embedded within the bilayer.
What are the types of membrane lipids?
-Phospholipids: most abundant. includes phosphoglycerides and sphingolipids.
-Glycolipids: a lipid + a carbohydrate group. includes cerebrosides and gangliosides.
-sterols: eukaryotic cells only. includes cholesterol and phytosterols.
What is the difference between simple diffusion, facilitated diffusion, and active transport?
simple diffusion: unaided movement of a solute down its concentration gradient
facilitated diffusion: protein aided movement of a solute down its concentration gradient
active transport: protein aided movement of a solute AGAINST its concentration gradient
define symport and antiport.
-symport: coupled transport in which both substances move the same direction
-antiport: coupled trasport in which substances move in opposite directions.
What are the six steps of the Na+/K+ pump?
1.) 3 Na are taken from inside
2.) ATP phosphorylates alpha subunits
3.) A conformational change following phosphorylation expels 3 Na to outside
4.) Two K+ accepted from outside
5.) Dephosphorylation triggers conformational change
6.) 2 K+ expelled to inside; pump returns to initial state.
What kind of pump does primary active use?
ATPase
What is symport or cotransport when referring to secondary active transport?
moving in the same direction as sodium
What is antiport when referring to secondary active transport?
moving in the opposite direction as sodium
Definition of flux
Movement of solute
What is a necessary requirement for osmosis
Semipermeable membrane
What stops movement of water in osmosis
Osmotic pressure
Hypotonic solutions make cells _____________
Swell - cells have more solute activity then solution

(blood cells-hemolyze)
Isotonic solutions do what to cells?
Preserve cell size - cells and solution have equal solute activity
Hypertonic solutions make cells _
Shrink - solution has more solute activity then cell
What regulates osmolarity of extracellular fluid
Kidneys in response to ADH
What is a nother name for transport proteins?
channel proteins
What is an aquaporin?
An aquaporin is a type of channel protein that allows the passage of water molecules
What do carrier proteins do?
they hold onto their passengers and change shape in a way that shuttles them across the membrane.
What is selective permeability?
the condition that allows some substances through more easily than others
Describe the current fluid-mosaic model of the membrane proposed by Singer and Nicolson.
Membranes are made of proteins bobbing in a fluid phospholipd bilayer. They are individually dispersed. The hydrophilic regions protrude and the hydrophobic regions are protected
How are membranes held together?
hydrophobic interactions (weaker than covalent bonds)
How does cholesterol affect fluidity in the membrane?
at warm temperatures it makes the membrane less fluid and make it so that it takes a lower temperature for them to solidify
Why is it so important for membranes to remain fluid?
when membranes are solid their permeability changes and enzymes might stop working
Diffusion of ions can create a separation of electrical charge across the membrane called a ______________
membrane potential. An electrochemical gradient can also be established.
Tonicity-
refers to the effect of an extracellular solution on the volume of the cells it surrounds.
Characteristics of membrane carriers
a. specificity –
b. saturation –
transport maximum (Tm) = maximum number of molecules that can be moved per unit time
c. competition –
. Facilitated diffusion –
a. the molecule binds to the carrier on the side of the membrane with the higher concentration
b. when the molecule binds to the carrier it causes the carrier to change shape
c. the molecule is released on the opposite side of the membrane
Solute pumps –
ATP provides energy to open the carrier on the low-concentration side of the membrane
Primary active transport -
the ATP that provides the energy is hydrolyzed by the primary transport carrier

example: Na/K-ATPase (the sodium-potassium pump)

a.phosphorylation (ATP) increases the carrier’s affinity for Na+ (inside the cell where the Na concentration is lower)
b.3 intracellular Na+ bind to carrier
c.carrier changes shape and is simultaneously dephosphorylated
d. dephosphorylation decreases carrier’s affinity for Na+ and increases affinity for K+
e.3 Na+ are discharged into tissue fluid, 2 extracellular K+ bind to carrier (outside the cell where the K+ concentration is lower)
f.carrier changes shape again and releases 2 K+ on inside of cell
. Secondary active transport
ATP works at one carrier to set up a concentration gradient for a molecule that will then be moved down its concentration gradient by a secondary carrier
the secondary carrier takes another molecule along with it (usually up its gradient)
Vesicular transport -
- used to move large polar molecules, droplets of fluid, or microbes across membranes

1.endocytosis
2. exocytosis
types of endocytosis:
a. phagocytosis - used for bacteria and debris
b. pinocytosis - used for engulfing fluid
c. receptor-mediated endocytosis - occurs after material to be transported binds to receptors on cell surface
Carrier-Mediated Transport--Molecules that cannot diffuse through the lipid bilayer or a channel may be transported by membrane carriers.
a.

b.

c.
Diffusion of ions Na, K, Cl, Ca---Through integral protein channels. What are the 4 types of channels
1.
2.
3.
4.
Phosphatidylinositol,
with inositol as polar head group, is one glycerophospholipid. In addition to being a membrane lipid, phosphatidylinositol has roles in cell signaling,
Sphingolipids
class of lipids derived from the aliphatic amino alcohol sphingosine. commonly believed to protect the cell surface against harmful environmental factors by forming a mechanically stable and chemically resistant outer leaflet of the plasma membrane lipid bilayer. Certain complex glycosphingolipids were found to be involved in specific functions, such as cell recognition and signaling. The first feature depends mainly on the physical properties of the sphingolipids, whereas signaling involves specific interactions of the glycan structures of glycosphingolipids with similar lipids present on neighboring cells or with proteins.
What are the four major phospholipid types?
Phosphotidylcholine, sphinogomyelin, phosphotidylserine, phosphotidylethanolamine
The variety of phospholipids in the membrane allows _______ for reactions.
specificity
The protein- and carboydrate-rich coating on the cell surface is called the __________.
glycocalyx
Calcium (Ca2+) is stored in high concentrations where?
Endoplasmic reticulum
In ______ junctions, nothing can diffuse between cells or past the junction.
Tight (occluding)
In _______ junctions, a series of proteins between cells connect one cell's cytoplasm to another's.
Anchoring
Gap junctions formed by proteins called _________, build tubes or pores between two cells so that ions and materials can pass between.
Connexins
Free ribosomes are found in the __________, while bound ribosomes are found in the outer membrane of the ___________.
Cytoplasm; rpugh endoplasmic reticulum
Smooth ER is involved in _______ synthesis and _________ of drugs and poisons.
Lipid; detoxification
Rough ER is involved in ______ synthesis via ________ lining its outer surface.
Protein; ribosomes
how are the proteins and lipids synthesized in the ER transported to the Golgi apparatus?
Through vesicles formed by budding of the ER membrane
What is the function of the Golgi apparatus?
To modify proteins (adding sugar groups) from the ER and repackaging them for delivery to lysosomes, the plasma membrane, or exterior of the cell
__________ contain hydrolytic enzymes involved in intracellular digestion of proteins, carbohydrates, and nucleic acids.
Lysosomes

-maintain a pH of 5 inside them
When are lysosomes useful?
To renew the cell's own components by breaking them down and releasing molecular building blocks into the cytosol, or to digest injured or dying cels
Peroxisomes contain _______ enzymes that break down ______ and ________ compounds such as alcohol.
oxidative, fats, detoxify
fluid portion of the cytoplasm ; approx. 55% of total cell volume(75-90% water plus various dissolved and suspended components)
cytosol
Three groups of inclusions:
Stored Food Substances, Pigments, Crystals
The ER, Golgi and mitochondria are held in their relative locations by attachment to the ________, especially to _______.
cytoskeleton, microtubules.
Virtually all proteins are synthesized on _________ in the cytosol. What is the one exception?
ribosomes; exception is a few mitochondrial proteins that are synthesized on ribosomes inside the organelles.
Name three different ways cytosolic proteins are transported across the membrane between compartments of the cell.
Gated, transmembrane, and vesicular transport
The nuclear envelope employs this type of protein transport
Gated transport; proteins moving from the cytosol to the nucleus are transported through NUCLEAR PORE COMPLEXES. Proteins do not need to unfold.
Nuclear pore complexes selectively transport specific macromolecules unidirectionally or bidirectionally? Active or passive transport of macromolecules?
Bidirectionally; Active transport, GTP required. Free diffusion of smaller molecules.
Ribosomes are/are not membrane bound.
Are not membrane bound.
These units are catalysts for protein synthesis within the cytoplasm of eukaryotic cells.
ribosomes
The lare and small subunit of ribosomes are manufactured in the ________ and released as separate entities into the cytosol.
Nucleolus
Proteins synthesized on _______ ribosomes include integral plasma membrane proteins, ER, golgi, and lysosomal proteins and proteins to be secreted from the cell.
Membrane-associated; make GLYCOSYLATED proteins which are segregated from the cytosol.
_____ ribosomes are responsible for synthesis of proteins destined for the nucleus, mitochondria, and peroxisomes, NON-GLYCOSYLATED.
Free or Membrane-nonassociated
Larger complexes like ribosomal subunits are transported through the nuclear membranes how?
recpetor-mediated transport, requires ATP.
Peroxisomes function in the catabolism of long chain fatty acids a process called _____. This process forms _____ as well as _______.
Beta oxidation; acetyl coA and hydrogen peroxide.
The double membrane that separates the nucleus from the cytoplasm is called the ______.
nuclear envelope
The process whereby lysosomes digest materials taken into the cell from its environment by endocytosis is called
Heterophagy
The process by which worn-out organelles are digested
autophagy
Based on size and chemical composition what are the three main types of filaments, in order of their decreasing diameter:
1. microfilaments
2. intermediate filaments
3. microtublues
Name some functions of the cytoskeleton
1. cell movement
2. support and strength for cell
3. phagocytosis
4. cytokinesis
5. cell to cell and cell to ECM adherence
6. changes in cell shape