2014 biochem

Question 1

What drives the pumping of H? (matrix -> intermembrane space):
A) Energy of redox reaction
B) Concentration gradient 
C) Electrochemical gradient
D) ATP hydrolysis

Answer 1

A) Energy of redox reaction

Question 2

what is true about the digestive process?

Answer 2

Pepsinogen activated autocatalysis

Question 3

Which enzyme provide proof-reading in translation?
A) Amino acid hydrolase
B) tRNA transferase
C) aa tRNA synthetase
D) Peptidyl transferase

Answer 3

C) aa tRNA synthetase

Question 4

What is (what is a characteristic of Satellite DNA?
A) Non coding transposons 
B) Non coding retrotransposons 
C) Non coding tandem repeats 
D) Non coding introns

Answer 4

C) Non coding tandem repeats

Question 5

Which of the following will be lacking in collagen if there is a Cu deficiency?
A) Cross bridges
B) Hydroxylation
C) S-S bonds
D) Hydrogen bonds

Answer 5

A) Cross bridges

Question 6

What is true about Transaminases?
A) They have pyridoxal phosphate as a cofactor
B) They are not reversible
C) They are not specific

Answer 6

A) They have pyridoxal phosphate as a cofactor

Question 7

Which of the following is involved in B-turns?
A) Proline
B) Glycine
C) Lysine
D) Glutamate

Answer 7

A) Proline

Question 8

Which of the following is true about glucagon? 
A) Increase glucose uptake by cells
B) decrease glucose synthesis
C) Increase glucose synthesis
D) Increase protein synthesis

Answer 8

C) Increase glucose synthesis

Question 9

What is the use of a microarray chip?
A) detecting misfolded proteins
B) gene expression profile

Answer 9

B) gene expression profile

Question 10

What is the cause of Alzheimer’s disease?

Answer 10

Abnormal protein processing

Question 11

What is associated with the inversion in the HEMA gene?
A) Severe hemophilia A
B) Mild hemophilia A
C) Severe hemophilia B
D) Blood clotting disorder

Answer 11

A) Severe hemophilia A

Question 12

What is used for mRNA 5'capping? 
A) GMP
B) CMP
C) AMP
D) UMP

Answer 12

A) GMP

Question 13

What best describes fatty acid synthase?
A) one enzyme molecule contains 6 enzymes and 1 protein
B) can synthesize a fatty acid molecule with a length up to 18C units
C) Forms antiparallel dimer to function

Answer 13

C) Forms antiparallel dimer to function

Question 14

Which of the following is mainly used as energy for gluconeogenesis in the liver?
A) Proteins
B) glycerol
C) Fatty acids

Answer 14

C) Fatty acids

Question 15

What happens after a meal during short period starvation (4-12 hours) to maintain the blood glucose levels?
A) glycogen breakdown
B) gluconeogenesis
C) lipolysis

Answer 15

A) glycogen breakdown

Question 16

What is the purpose of the glucose alanine cycle?
A) Eliminate nitrogen from the muscles
B) Decrease ammonia excretion by the liver

Answer 16

A) Eliminate nitrogen from the muscles

Question 17

What is the product of non-oxidative stage of Pentose phosphate pathway?
A) glucose 6-phosphate
B) ribose-5-phosphate
C) NADPH

Answer 17

B) ribose-5-phosphate

Question 18

What’s a characteristic of trans fat?
A) can only be produced artificially but not naturally
B) can be produced in our body in beta-oxidation

Answer 18

B) can be produced in our body in beta-oxidation

Question 19

What is the substrate for glycogen synthase?

Answer 19

UDP-glucose

Question 20

which of the following is a main product of catabolism?
A) NAD+
B) NADH
C) NADP+

Answer 20

B) NADH

Question 21

a patient suffers from glycogen storage disease type Ia (Von Gierke disease). This disease can result from a deficiency in glucose 6-phosphatase. What is the patient most likely going to suffer?
A) hypoglycemia
B) normal growth
C) normal blood sugar levels

Answer 21

A) hypoglycemia

Question 22

What is a characteristic of cooperativity in enzymes?

Answer 22

has more than one catalytic site

Question 23

what is the Consequence of high Vmax of glucokinase?
A) To allow rapid uptake of glucose by the liver after a meal
B) Preventing hypoglycemia
C) Rapid synthesis of glucose when it’s levels are low
D) rapid release of glucose cuz it will have higher capacity

Answer 23

A) To allow rapid uptake of glucose by the liver after a meal

Question 24

The signal peptide of a lysosomal protein was cleaved in the ER, where will the protein go? 
A) lysosome 
B) secretion 
C) nucleus 
D) Golgi

Answer 24

A) lysosome

Question 25

What is a characteristic of DNA euchromatin?
A) actively transcribed
B) highly acetylated
C) highly methylated

Answer 25

A) actively transcribed

Question 26

Why can’t we detect the template DNA in PCR?

Answer 26

it remains unamplified

Question 27

Which of the following processes tRNA?

Answer 27

RNase p

Question 28

Which of the following is removed from the exterior of the cytoplasmic membrane by floppase (flippase)?
A) Phosphatidylserine
B) phosphatidylcholine

Answer 28

A) Phosphatidylserine

Question 29

what fat substitute is not digested in our body?

Answer 29

olestra (a fat substitute that adds no fat, calories, or cholesterol to products)

Question 30

What are the restriction enzymes?
A) They protect the bacteria as they cut the foreign DNA
B) They cut the bacterial DNA because it is methylated
C. They cut the viral DNA because it is methylated

Answer 30

A) They protect the bacteria as they cut the foreign DNA

Question 31

which of the following affects the annealing temperature?

Answer 31

the primer length and sequence