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Flashcards in Bio Deck (49):
1

The tendency of the body to oppose flow is known as ________.

The tendency of the body to oppose flow is known as resistance.

2

Stenosis, or narrowing, of the afferent arteriole would cause a(n) _______ in resistance because of the reduced diameter of the afferent arteriole

Stenosis, or narrowing, of the afferent arteriole would cause an increase in resistance because of the reduced diameter of the afferent arteriole

3

The outside of a cell has a net ____ charge

The outside of a cell has a net + charge, more Na+ and less K+ (3 Na+ out, 2 K+ in)

4

 The resting membrane potential of neurons is approximately ____ mV, which is close to K+ resting potential.

 The resting membrane potential of neurons is approximately −70 mV, which is close to K+ resting potential.

5

What is the initial rise in the action potential due to?

Na+

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6

What cells are myelin sheaths produced by?

Glial cells

7

What kind of channels are found at the nodes of Ranvier in myelinated axons?

Voltage-gated ion channels are clustered at the nodes of Ranvier; in unmyelinated axons, they are evenly distributed 

8

How do electrical synapses transfer information?

Electrical synapses transfer information from one cell to another via passive ionic current flow through gap junctions almost instantaneously since the cells are continous 

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9

Explain the steps in a chemical synapse

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10

Is the cytosol side hydrophobic or hydrophillic?

Hydrophillic 

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11

What amino acid are serine and threonine very similar to?

Alanine

12

Which amino acids have amide groups?

Asparagine and glutamine 

13

How does SDS page separate proteins?

By size

 

(anode is the + side)

14

Which mRNA functions in RNA interference by binding target complementary seq on mRNA molecule to silence gene expression?

miRNA

15

Which RNA associates with specific proteins to form snRNPs, the building blocks of spliceosomes?

snRNA

16

Which RNA functions in RNA interference by binding complementary mRNA and signals for its degredation?

siRNA

17

Which way does Km and Vmax increase in a Lineweaver Burk plot?

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18

Fatty acid synthesis is an anabolic process that builds lipids in the ____.  Anabolic processes generally require precursor molecules: ATP, NADPH, and acetyl-CoA, respectively.

 

In this process NADPH is oxidized to NADP+

Fatty acid synthesis is an anabolic process that builds lipids in the cytosol.  Anabolic processes generally require precursor molecules: ATP, NADPH, and acetyl-CoA, respectively.

 

In this process NADPH is oxidized to NADP+

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19

β-oxidation is the breakdown of fatty acid chains into _____ through a series of oxidation reactions in the mitochondrial matrix that produce ATP;  long-chain fatty acids obtained from lipid stores must undergo a set of reactions to enter the mitochondrial matrix.

β-oxidation is the breakdown of fatty acid chains into acetyl-CoA through a series of oxidation reactions in the mitochondrial matrix that produce ATP;  long-chain fatty acids obtained from lipid stores must undergo a set of reactions to enter the mitochondrial matrix.

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20

During fatty acid synthesis, acetyl-CoA in the mitochondria is converted into ____ and then transported into the cytoplasm, where it is reconverted into acetyl-CoA and oxaloacetate.  

During fatty acid synthesis, acetyl-CoA in the mitochondria is converted into citrate and then transported into the cytoplasm, where it is reconverted into acetyl-CoA and oxaloacetate.  

21

During β-oxidation, long-chain fatty acids are activated with _____ and shuttled by enzymes from the cytoplasm to the mitochondrial matrix.  The rate-limiting step of fatty acid oxidation is the conversion of fatty acyl-CoA molecules into ______ by carnitine acyltransferase I.

During β-oxidation, long-chain fatty acids are activated with coenzyme A and shuttled by enzymes from the cytoplasm to the mitochondrial matrix.  The rate-limiting step of fatty acid oxidation is the conversion of fatty acyl-CoA molecules into fatty acylcarnitine by carnitine acyltransferase I.

22

Insulin _____ lipid synthesis by activating the major enzymes involved in fatty acid production:  Pyruvate dehydrogenase complex, acetyl-CoA carboxylase, and fatty acid synthase.

Insulin stimulates lipid synthesis by activating the major enzymes involved in fatty acid production:  Pyruvate dehydrogenase complex, acetyl-CoA carboxylase, and fatty acid synthase.

23

_____ amino acids are converted to pyruvate or citric acid cycle intermediates, which can be converted to glucose.  _____ amino acids are converted directly to acetyl-CoA, which can enter the citric acid cycle or be used to form ketone bodies.  

 Glucogenic amino acids are converted to pyruvate or citric acid cycle intermediates, which can be converted to glucose.  Ketogenic amino acids are converted directly to acetyl-CoA, which can enter the citric acid cycle or be used to form ketone bodies.  

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24

What are the functions of the spleen?

Filters damaged RBCs, reservoir for blood, immune response (B cell activation, houses macrophages)

25

Does Gel 1 or Gel 2 represent non-reducing SDS-page?

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Gel 1 is non-reducing

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26

______ is a molecular technique used to determine the nucleotide order of DNA molecules.

DNA sequencing is a molecular technique used to determine the nucleotide order of DNA molecules.

27

______ is an RNA assay used to assess gene expression in different tissues.

Northern blotting is an RNA assay used to assess gene expression in different tissues.

28

Does vasocontriction or vasodilation increase blood pressure?

Vasoconstriction 

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29

Which bond, cis or trans, increases membrane fluidity? 

Cis - this configuration is particularly important in cell membranes as it introduces a bend or "kink" in the fatty acid that prevents phospholipids from stacking together and solidifying.

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30

Each phospholipid has a unique ____, ____, and _____ due to distinct features in the backbone, polar head groups, and fatty acid chains.

Each phospholipid has a unique mass, charge, and solubility due to distinct features in the backbone, polar head groups, and fatty acid chains.

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31

What are examples of hydrolyzable lipids and non-hydrolyzable lipids?

(Note: all lipids can be emulsified)

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32

What is Kcat = to?

Kcat = vmax / E total

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33

 Reactions in which n > 1 display _____ cooperativity whereas reactions where n = 1 or n < 1 exhibit ____ cooperativity or _____ cooperativity, respectively.

 Reactions in which n > 1 display positive cooperativity whereas reactions where n = 1 or n < 1 exhibit no cooperativity or negative cooperativity, respectively.

34

T/F: cell membranes are composed largely of phospholipids, which act as a fluid that allows other membrane components such as transmembrane proteins, glycoproteins, cholesterol, and glycolipids to migrate through this environment laterally.

T: cell membranes are composed largely of phospholipids, which act as a fluid that allows other membrane components such as transmembrane proteins, glycoproteins, cholesterol, and glycolipids to migrate through this environment laterally.

35

The secretory pathway involves the processing of proteins as they go through the _____ and the ____.  After processing in the Golgi, proteins destined for the cell membrane are packed into secretory vesicles, which fuse with the plasma membrane. 

The secretory pathway involves the processing of proteins as they go through the endoplasmic reticulum and the Golgi apparatus.  After processing in the Golgi, proteins destined for the cell membrane are packed into secretory vesicles, which fuse with the plasma membrane. 

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36

_____ can participate in retrograde trafficking, which refers to the reversal of a pathway in the context of cellular trafficking.  In this case, retrograde trafficking leads to endosomes producing vesicles that fuse with the Golgi apparatus.

Endosomes can participate in retrograde trafficking, which refers to the reversal of a pathway in the context of cellular trafficking.  In this case, retrograde trafficking leads to endosomes producing vesicles that fuse with the Golgi apparatus.

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37

Which glycolysis intermediate could serve as the sole starting material of the synthesis of R5P in muscle tissue? 

 

a. Fructose 6 phosphate

b. Glyceraldehyde 3 phosphate

c. fructose 1, 6 bisphosphate

d. dihydroxyacetone phoephate

a. Fructose 6 phosphate

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38

The free energy available in each ATP molecule is ___ kJ/mol

The free energy available in each ATP molecule is −30 kJ/mol

39

_____ is the enzyme in the pentose phosphate pathway that catalyzes the conversion of 6-phosphogluconate to R5P.  

6-Phosphogluconate dehydrogenase (6PGD) is the enzyme in the pentose phosphate pathway that catalyzes the conversion of 6-phosphogluconate to R5P.  

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40

Are D-mannose and D-glucose:

a. epimers

b. enantiomers

c. constiutional isomers

d. anomers

a. epimers; only differ at 1 stereocenter

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41

____ are stereoisomers that differ at every stereocenter, not just one. 

Enantiomers are stereoisomers that differ at every stereocenter, not just one. 

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42

All monosaccharides are reducing sugars. What are two examples?

Galactose and ribose

43

Lactose is a _____ sugar

Lactose is a _____ sugar; it has a free anomeric carbon (NOTE: SUCROSE IS A NON-REDUCING SUGAR)

44

Histidine (H) can contribute only a ____ charge to a peptide, so it can only increase pI.

Histidine (H) can contribute only a positive charge to a peptide, so it can only increase pI.

45

Ionizable side chains that contain oxygen or sulfur (__, __, __, __) are negatively charged when deprotonated and tend to decrease pI.

Ionizable side chains that contain oxygen or sulfur (Y, C, E, and D) are negatively charged when deprotonated and tend to decrease pI

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46

A drop in BP causes the juxtaglomerular cells in the kidneys to release ____, an enzyme that cleaves the plasma protein angiotensinogen to form angiotensin I.  

A drop in BP causes the juxtaglomerular cells in the kidneys to release renin, an enzyme that cleaves the plasma protein angiotensinogen to form angiotensin I.  

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47

 Angiotensin-converting enzyme (ACE) cleaves ____ to form _____, which ultimately raises BP by inducing both the release of aldosterone from the adrenal cortex and the constriction of arterioles.

 Angiotensin-converting enzyme (ACE) cleaves angiotensin I to form angiotensin II, which ultimately raises BP by inducing both the release of aldosterone from the adrenal cortex and the constriction of arterioles.

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48

Long-chain fatty acids are not recognized by any transport proteins; they must be modified or "activated" to enter the matrix.  Fatty acid activation and transport requires which of the following:

a. ATP

b. OAA

c. carnitine

d. coenzyme A

a. ATP

c. carnitine

d. coenzyme A

 

In the cytosol, acyl-CoA synthetase catalyzes the reaction with coenzyme A to form acyl-CoA and requires ATP hydrolysis to proceed...

Acyl-CoA molecules then migrate to the intermembrane space and react with carnitine to form acylcarnitine.  Acylcarnitine translocase recognizes acylcarnitine and carries it into the mitochondrial matrix...

Acylcarnitine is then converted back to acyl-CoA and carnitine.  Acyl-CoA is digested by β-oxidation, and carnitine transported out of the matrix where it can pick up and carry a new fatty acid into the mitochondrial matrix.

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