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All of the following decrease the affinity of hemoglobin for oxygen EXCEPT: A. Carbon monoxide B. pH below 7 C. Presence of 2-3 Bisphosphoglycerate D. Carbon Dioxide

A

1

Which of the following would increase the P50 in the oxygen-hemoglobin saturation curve?
A. Decreased temperature
B. Decreased carbon dioxide
C. Decreased pH
D. Decreased 2,3 bisphosphoglycerate

C

2

Which of the following directly influences a solution’s power of hydrogen?
A. Concentration of hydroxide ions
B. Concentration of protons
C. Mass of hydroxide ions
D. Mass of hydrogen ions

B

3

The following acids have corresponding pKas: X = 3.5, Y = 7, Z = 7.2. Which of the following is considered the weakest acid?
A. X
B. Y
C. Z
D. the data is incomplete for a conclusion

A

4

The following are lipid components of membranes, except:
A. gangliosides
B. sphingomyelin
C. cholesterol
D. triacylglycerol

D

5

A certain disease is due to the formation of salt bridges between amino acids within an important protein. Which of the following amino acids might be responsible for the disease?
A. Glutamate and cysteine
B. Cysteine and methionine
C. Lysine and aspartic acid
D. Alanine and phenylalanine

C

6

The process of translation is responsible for which of the following?

A. Producing a fully functional protein molecule
B. Creating a single strand of mRNA molecule
C. Enabling post-translational modifications to occur
D. Linking amino acids together via peptide bonds

D

7

Which of the following events is TRUE regarding denaturation of proteins?
A. Denaturation happens when you mix proteins and detergents
B. Denaturation means destruction or unraveling of the protein’s peptide bonds
C. It is a permanent, spontaneous event
D. It needs chaperones to facilitate a speedy reaction

A

8

which among the following amino acids will you most probably see at the center of the hypothetical amino acid blob?

A. Valine and tryptophan
B. Arginine and cysteine
C. Serine and threonine
D. Asparagine and aspartic acid

A

9

The lipid bilayer can be best described as p

A. Composed mostly of proteins with interspersed lipid and carbohydrate molecules
B. A barrier disallowing the passage of most water-soluble molecules
C. Composed of a layer of phospholipids arranged concentrically D. A barrier allowing ions such as Cl- to freely pass through

C

10

The sequence of the first amino acids of polypeptide 1 is EWAN while those of two polypeptide is MALAY. Which of The following statement is TRUE regarding the protein structure?

A. it is a homodimer
B. the primary structure of each polypeptide is defined as an alphahelix
C. hydrogen bonds are responsible for the secondary structure D. this protein can be considered insoluble in water

C

11

A protein in its denatured state:

A. loses its biologic activity
B. becomes more soluble in an aqueous solution
C. is hydrolyzed to its constituent amino acids
D. all of the above

A

12

Rate limiting SUBSTRATE(not the same sa Enzyme ah ) of Purine synthesis

PRPP

13

Ratelimiting enzyme of purine synthesis

PRPP-Gln Amidotransferase

14

Rate limiting enzyme and most impt. enz in glycolysis

PFK

15

For glycogenesis

Glycogen synthase/synthetase

16

For glycogenolisis

Glycogen phosphorylase

17

Rate limiting enzyme ng gluconeogenesis

fructose 2,6 bisphosphatase

18

The only cell in our body which is capable of utilizing ONLY GLUCOSE for its source of energy

RBC

19

also uses fatty acids as its source of energy

Heart

20

Liver - produces ketones but does not use it bec. it lacks the enz

3-ketoacyl transferase

21

Vit D Def in adults

Osteomalacia

22

Function of vit B5

active form: constituent of Coenzyme-A
- used as cofactor for acyl transferase
- component of fatty acid synthase

23

Products of PPP

Ribose-5-phosphate and
NADPH

24

used for purine/pyrimidine (nucleotide) synthesis

Ribose 5 posphate

25

Def. of vit b1

Beriberi

26

Carbs to fats - yes, bec. of

Pyruvate dehydrogenase

27

Fats to carbs - no bec. rxn of

PDH is irreversible
One way

28

ATP acts as an allosteric activator of

aspartate transcarbamoylase (ATCase

29

Which of the following two enzymes are thought to be the major control enzymes of the TCA cycle

α-ketoglutarate dehydrogenase and isocitrate dehydrogenase

30

ATP acts as an allosteric activator of aspartate transcarbamoylase (ATCase). This means that

A. The substrate saturation curve for Aspartate and ATCase shifts to the left, signifying increased affinity of ATCase for its substrate

31

True of phosphofructokinase

A. It is inhibited when the cell is rich in ATP

32

True of the citric acid cycle

It is involved in both anabolic and catabolic cellular pathways

33

How many ATP can be formed from 1 mole of acetyl CoA that enters the citric acid cycle

10

34

Glycogen synthase adds glucose residues to the glycogen primer in the form of

UDP glucose

35

What is the effect of cAMP-dependent protein kinase on the following enzymes involved in glycogen metabolism

A. activates phosphorylase kinase and inhibitor-1; inactivates glycogen synthase (NOT SURE IF THIS IS INCLUDED IN OUR FINAL EXAM

36

Unlike liver glycogen, muscle glycogen cannot be used for the maintenance of blood glucose level because muscles lack

Glucose 6 phosphate

37

C2 of Purine

N10 - Formyl THF

38

C2 of Pyrimidine

CO2

39

Von Gierke's Disease

Glucose-6phosphate-dehydrogenase

40

Cytochrome P450 is involved in the synthesis of this hormone

Aldosterone

41

How many high energy phosphates does ATP have

2

42

Which of the following has the highest affinity for electrons

Oxygen

43

The growing fatty acid chain on the fatty acid synthase complex is elongated

two at a time, with the carbons added derived from malonyl-CoA

44

Odd-chain long fatty acid breakdown produces

BOTH acetyl-coA and ProprionylcoA

45

Which of the following uses fatty acids as its primary source of energy in the well-fed state

Heart

46

In the citrate shuttle, citrate is transported from the mitochondria to the cytoplasm in exchange for which of the following

Malate

47

Which of the following carries trigylcerides from the INTESTINES to the adipose tissues

Chylomicrons

48

Degradation of ketone bodies would yield which of the following

Acetyl Coa

49

Glucagon stimulates

A. Fatty acid esterification in adipose tissues B. activation of hormone sensitive lipase C. Both A and B D. Neither A nor B

50

An 18-carbon monounsaturated fatty acid in trans configuration

Elaidic acid

51

The facial flushing and rapid heart rate associated with intake of alcoholic beverages is due to the increased level of

ACETALDEHYDE

52

The density of the lipoproteins is directly proportional to

A. the total concentration of the lipid component
B. the concentration of cholesterol and cholesteryl ester
C. the concentration of triacylglycerol
-D. the concentration of the protein component

53

True of Cholesterol

Its esterified form is a major constituent of the plasma membrane B. It is an alternative source of ATP via betaoxidation in the absence of free fatty acids
-C. Its free form is amphipathic
D. All of the above

54

What is the difference between fatty acid synthesis and cholesterol synthesis

D. The final product in fatty acid synthesis is a 16- carbon compound while the final product in cholesterol synthesis is a 27-carbon compound

55

True of bile acids

When conjugated, they become more water soluble