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Flashcards in FINAL FINAL Deck (63)
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1

Glutamate and α-ketoglutaric acid, as well as oxaloacetic acid and aspartic acid, are especially important in carbohydrate metabolism because:

They allow a way to add intermediate molecules to the TCA cycle 

2

Tyrosine is a non-essential amino acid because we can synthesize it from:

Phenylalanine

3

S-Adenosylmethionine is used in synthetic reactions to:

Provide methyl groups for synthesis reactions

4

We need daily supplies of many vitamins, including folic acid. For what purpose or purposes do we need folic acid?

To carry one-carbon fragments during metabolism 

5

Transamination of amino acids results in products called:

α-keto acids

6

Ketogenic amino acids are broken down to acetoacetate or

acetyl-CoA (or Pyruvate)

7

The amino acids Ala, Cys, Gly, Ser, and Thr are all degraded to the metabolite 

pyruvate

8

Which of the following glycolytic intermediates is the common precursor to serine, cysteine, and glycine?

3-phosphoglycerate

9

The neurotransmitters DOPA, dopamine, epinephrine, and norepinephrine are synthesized from the amino acid 

tyrosine

10

Nitrogenase carries out the reaction that reduces nitrogen to 

NH3

11

When glutamate is oxidatively deaminated by GDH, the products include 

NAD(P)H + H+, NH4+, and a-ketoglutarate

12

In which cellular compartment does the following reaction take place?

arginine —> urea + ornithine

cytosol

13

In which cellular compartment does the following reaction take place?

ornithine + carbamoyl-phosphate —> citrulline

 

 

mitochondrial matrix

14

In the reaction depicted below, choose the right answer:

A)The reaction is involved in the protein synthesis where 1=carbamoyl synthetase, and 2=carbamide phosphate

B)The reaction is the committed step of the urea cycle where 1=carbamoyl phosphate synthase, and 2=carbamoyl phosphate

C)The reaction is a side product of the urea cycle, and 1=carbamoyl phosphate synthase, and 2=carbamoyl phosphate

D)A) and C)

The reaction is the committed step of the urea cycle where 1=carbamoyl phosphate synthase, and 2=carbamoyl phosphate

15

The metabolite chorismate

is an important intermediate in the production of Trp, Tyr, Phe

16

Which of the following reactions is catalyzed by adenylate cyclase?

ATP → cAMP + PPi

17

How do steroid hormones influence gene expression?

They bind receptor in the cytosol. These complexes then migrate to the nucleus where they bind hormone response elements to affect transcription

18

Phospholipase C cleaves PIP2, generating

IP3 and DAG (inositol-1,4,5-trisphosphate and 1,2-diacylglycerol)

19

During  fasting and prolonged starvation, skeletal muscle

Protein is degraded to provide amino acids to the liver for gluconeogenesis

20

Which of the following are effects of insulin secretion?

A)Muscle and adipose tissue are stimulated to take up glucose;

B)Gluconeogenesis is inhibited in the liver and kidney;

C)Synthesis of glycogen, proteins, and triacylglycerols are stimulated, promoting cell growth;

D)A and B;

E)A, B, and C

 

E)A, B, and C

21

The functions of the kidney include all of the following except

A) Blood pH regulation;

B) Body water regulation;

C) Reabsorption of electrolytes, sugars, and amino acids from the urinary filtrate;

D) Filtration of blood plasma which results in the excretion of water-soluble waste products;

E) Production of urea from ammonia

Production of urea from ammonia

22

A simple system for information flow is composed of three components : reception, transduction and response.  In multicellular organisms hormones play a role in which phase?

Reception

23

The IP3 receptor

Is a calcium channel

24

What types of molecules serve as the starting materials for synthesis of uric acid?

Purine bases

25

Ubiquinated proteins are transferred to large proteolytic machines for cleavage to smaller fragments. The proteolytic machine is known as a:

Proteasome

26

Calmodulin is a 

Calcium-binding protein

27

The liver performs all of the following functions except

Storage of energy in the form of fat

28

Degradation of proteins is facilitated by a process known as:

Ubiquination

29

Brain tissue normally consumes glucose, but when glucose levels are low, nervous tissue can also consume:

β-hydroxybutyrate and acetoacetic acid

30

Peptide hormones which bind to G-protein-coupled receptors stimulate the activity of adenyl cyclase, producing a second messenger called:

Cyclic-3'5'-adenosine monophosphate