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GLYCOLYSIS:

Multiple Choice Questions:

1. Which stage in the metabolic pathway is ATP generated as  a NET gain for the cell?

a. glucose to glucose 6-phosphate

b. fructose 6-phosphate to fructose 1,6-bisphosphate

c. fructose 1,6-bisphosphate to glyceraldhyde 3-phosphate

d. 1,3-bisphosphoglycerate to 3-phosphoglycerate

e. phosphoenolpyruvate to pyruvate

2. Phosphorylation of glucose and its conversion to glyceraldhyde 3-phosphate refers to:?

a. energy generation phase

b. pay off phase

c. energy conservation phase

d. preparatory phase

e. energy splitting phase

3. Which of the following enzymes does not have a delta G that is close to zero (0) where it is not in equilibrium?

a. hexokinase

b. aldolase

c. enolase

d. pyruvate kinase

e. phosphoglycerate kinase

4. What is the  name of the enzyme that catlyses the only oxidation reaction in glycolysis?

a. phosphoglycerate kinase

b. glyceraldehyde 3-phosphate dehydrogenase

c. triose phosphate immerase

d. aldolase

e. phosphoglycerate mutase

5. Converting one molecule of glucose to two molecules of pyruvate yields a total of ____ ATP?

a. 1

b. 2

c.3

d. 4

e. 5

6. Glucolysis occurs in the __________ ?

a. mitochondria

b. nucleus

c. cytoplasm

d. cytosol

e. golgi apparatus

7. Which of the follwing enzyme is the most regulated in glycolysis and controls the second priming effect ?

a.  aldose

b. hexokinase

c. phosphohexose isomerase

d. phosphofructokinase

e. pyruvate kinase

8. Why is glucose 6-phosphate more important than glucose molecules itself?

a. no transporters for the form

b. only glucose is transported across

c. phosphorous is attached to ATP

d. becomes unstable and promotes the reaction

e. all of the above

True and False:

1. Under aerobic conditions, the end-product of glycolysis is further reduced to yield more ATP.

2. Galactose being a sugar like glucose can be converted to pyruvate in the cytosol.

3. Glyceraldehyde 3-phosphate and dihydroxyacetone phosphate are isomers of each other.

4. TIM is a kinetically perfect enzyme.

5. The active site allows the entrance of water molecules so hydrolysis can take place instead of phosphorylation.

ENZYMES MCQ

Select the correct multiple answer using ONE of the keys A, B, C, D or E as follows:

A. 1, 2 and 3 are correct

B. 1 and 3 are correct

C. 2 and 4 are correct

D. only 4 is correct

E. all are correct

 

Ribozymes satisfy several enzymic criteria such as:

  1. they enhance the reaction rate
  2. they emerge from the reaction specific
  3. they are substrate specific
  4. they are catalytic RNAs

Enzymes are made up of:

  1. 90% protein 10% DNA
  2. 80% protein 20% DNA
  3. 80% protein 20% RNA
  4. 90% protein 10% RNA

Which of the following has a catalytic power?

  1. Enzymes
  2. Alozymes
  3. Apoenzymes
  4. Ribozymes

Why are enzymes considered to be versatile biochemical catalysts?

  1. Catalyze reactions 103 to 108 times faster than uncatalysed reactions
  2.  They are biological catalysts that speeds up a chemical reaction by lowering the activation energy
  3. Transforms 100 to 1000 substrate molecules into product each second
  4. They are protein in nature

What are cofactors?

  1. Non protein contents
  2. Organic and inorganic coenzymes
  3. Used in the formation of holoenzymes
  4. Protein contents

Why are inorganic catalysts less efficient than biological catalysts?

  1. Require lower temperatures between 35-37 oC
  2. It is guarantee of 100% yield
  3. The catalysts can be regulated
  4. They produce side reactions and wasteful by-products

The interactions between the active site and substrate occur because of:

  1. Hydrophobic interactions
  2. Hydrogen bonding
  3. Van der walls forces
  4. Electrostatic interactions

Temperature, [E] and pH is correctly represented by:

mcq

 What bond is found in thermophilic bacteria?

  1. Disulphide bonds
  2. Hydrogen bonds
  3. Hydrophobic interactions
  4. Peptide bonds

Changes in pH results in:

  1. –NH3+ + OH  → –NH2 + H2O
  2. –COO+ H+ → COOH
  3. 30 is affected and protein is denatured
  4. the NH3+ –COO charges attracting each other is disrupted

The assumptions for the MM curve are:

  1. [S] is greater than the [E]
  2. [ES] does not change with time
  3. Rate of the reaction is measured as the substrate and enzyme mix
  4. Km is the [S] at which velocity is equal to a half of Vmax

Allosteric enzymes are characterized by which of the following?

  1. Having more than one active site
  2. Cooperatively bind substrate molecules
  3. Induces a conformational change
  4. Alters the affinity of other active sites

AMINO ACIDS AND PROTEINS

TRUE / FALSE

  1. All proteins have both a primary and secondary structure.
  2. Denaturing proteins disrupts their primary structures only.
  3. Urea is a chaotrope which disrupts the hydrophobic interactions causing the protein to loose its tertiary structure.
  4. A typical amino acid has an amino group, a hydrogen atom and a carbonyl group bonded to a central carbon.
  5. The biuret test is only done to determine the presence of proteins not amino acids in a solution.

MULTIPLE CHOICE QUESTIONS

1. How many different types of amino acids are present?

a. 3

b. 20

c. 100

d. 120

e. none of the above

2. Which of the following forces is the most unfavorable for protein folding?

a. Covalent bonding

b. Vander Waals interactions

c. Conformational entropy

d. Hydrophobic interactions

e. Electrostatic interactions

3. An essential amino acid is one that:

a. readily available in the body

b. the body can synthesize

c. is essentially easy to synthesize

d. the body cannot synthesize

e. none of the above

4. The sequence of letters ‘KNQG’ will represent:

a. alanine, cysteine, proline, glycine

b. lysine, asparagine, glutamine, glycine

c. asparagine, lysine, glycine, glutamine

d. histidine, glycine, asparagine, valine

e. asparagine, glutamine, histidine, glycine,

5. The sulphur containing chain of cysteine is:

a. hydrophobic, highly reactive and capable of reacting with another cysteine

b. hydrophillc, highly reactive and capable of reacting with another cysteine

c. amphiphilic, not reactive with another cysteine

d. amphiphilic, highly reactive and capable of reacting with another cysteine

e. none of the above

6. Which amino acid when exposed to Ninhydrin produces a brown colour?

a.  alanine

b. valine

c. asparagine

d. proline

e. glycine

7. Beta pleated sheets are examples of protein’s:

a. primary structure

b. secondary structure

c. tertiary structure

d. quaternary structure

e. α – helix configuration

8. Sickle cell disease is due to:

a. a mutation in the beta chain of hemoglobin

b. mutation in the secondary structure between Glu and Val residues

c. a mutation in the alpha chain of hemoglobin

d. infection with a parasite

e. none of the above

9. Which one of the following is an essential amino acid?

a. alanine

b. cysteine

c. asparagine

d. glycine

e. valine

10. If an egg white protein of albumin is denatured into a hard boiled egg then which of the following is least affected?

a. the primary structure of ovalbumin

b. the secondary structure of ovalbumin

c. the tertiary structure of ovalbumin

d. the quaternary structure of ovalbumin

e. none of the above

11. Disulphide bonds are formed between:

a. between two cysteine residues

b. between two cystine residues

c. between a alanine and asparagine residue

d. between two glycine residues

e. none of the above

12. Alpha helicies in the secondary structure of proteins are affected by:

a. the interactions between R groups spaced 3 or 4 residues apart

b. the electrostatic repulsion or attraction between successive amino acid residues with charged R groups

c. the bulkiness of adjacent R groups

d. the occurrence of Pro and Gly

e. all of the above

13. The four subunits of hemoglobin represents:

a. primary structure

b. secondary structure

c. tertiary structure

d. quaternary structure

e. none of the above

14. The α-amino acids have a carboxyl group with a pK around __________ , and an amino group with a pK near __________ .

a. 7.0 and 9.0

b. 5.5 and 12.1

c. 2.2 and 9.4

d. 1.0 and 6.3

e. 0.5 and 11.0

15. Refer to the diagram below. Choose the correct answer:Image

a. parallel beta pleated sheet & anti parallel alpha pleated sheet

b. parallel beta pleated sheet & anti parallel beta pleated sheet

c. anti parallel beta pleated sheet & parallel alpha pleated sheet

d. anti parallel beta pleated sheet & parallel beta pleated sheet

e. none of the above

Select the correct multiple answer using ONE of the keys A, B, C, D, or E as follows:

A. 1, 2, and 3 are correct

B. 1 and 3 are correct

C. 2 and 4 are correct

D. only 4 is correct

E. all are correct

Amino acids with positively charged R groups include:

  1. Arginine
  2. Histidine
  3. Lysine
  4. Aspartate

CARBOHYDRATES

Multiple Choice Questions:

1) Why is it that sucrose is the only non-reducing sugar while maltose and lactose which are also disaccharides are reducing sugars?

a.  sucrose is made up of glucose and fructose

b.  sucrose bonding is an alpha (1-2) linkage

c.  sucrose has only one free anomeric carbon

d.  sucrose comprises of glycosidic bonds between C1 and C2

e.  sucrose anomeric carbons are both involve d in bonding

2) The polysaccharides that contain alpha linkages are:

a.  starch

b. sucrose

c.  cellulose

d.  glycogen

e. cellobiose

Select the correct multiple answer using ONE of the keys A, B, C, D or E as follows:
A. 1, 2 and 3 are correct
B. 1 and 4 are correct
C. 2 and 5 are correct
D. only 4 is correct
E. all are correct

143994e2d22ed00ec7

By: Neermala Ragoonanan

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