QUESTION 1

1. Muscles can use ketone bodies, glucose, and fatty acids for energy.

   True

   False

1 points   

QUESTION 2

1. Lysine and arginine are the only purely ketogenic amino acids.

   True

   False

1 points   

QUESTION 3

1. Arginine is a precursor for the synthesis of nitric oxide, a free radical gas.

   True

   False

1 points   

QUESTION 4

1. If thrown into a lake, a 10-pound slab of butter would sink to the bottom.

   True

   False

1 points   

QUESTION 5

1. Certain saturated fatty acids are called ‘essential fatty acids’ (EFAs) because we cannot synthesize them, yet we need them for several key biological functions.

   True

   False

1 points   

QUESTION 6

1. Cholesterol esters are weakly amphipathic.

   True

   False

1 points   

QUESTION 7

1. For a protein to be efficiently degraded by the proteasome, it must first be polyubiquitinated.     

   True

   False

1 points   

QUESTION 8

1. Animals are dependent on plants and certain microorganisms for the synthesis of nitrogen-containing organic compounds.

   True

   False

1 points   

QUESTION 9

1. Endogenous TAGs and fatty acids are carried to the liver by chylomicron remnants.

   True

   False

1 points   

QUESTION 10

1. The surface lipids and proteins of lipoprotein particles have many covalent bonds between them that stabilize the particles during transport through the bloodstream.

   True

   False

1) How many ATP molecules are consumed in the hexose stage of glycolysis for every one molecule of glucose?

A) 0; ATP is produced, not consumed, by glycolysis.

B) 1

C) 2

D) 3

E) 4

2) During glycolysis, isomerization occurs during which of the following reactions?

A) Fructose 1,6-bisphosphate → dihydroxyacetone phosphate and glyceraldehyde 3-phosphate.

B) Fructose 6-phosphate → fructose 1,6-bisphosphate.

C) Glucose 6- phosphate → fructose 6- phosphate.

D) Glucose → glucose 6- phosphate.

3) An intramolecular phosphoryl-group transfer occurs when

A) 2-phosphoglycerate is converted to phosphoenolpyruvate.

B) 1,3-bisphosphoglycerate is converted to 3-phosphoglycerate.

C) Both A and B.

D) None of the above.

5) Glucose 6-phosphate allosterically inhibits

A) hexokinase I.

B) glucokinase.

C) hexokinase II.

D) All of the above

E) A and C only

6) Glyceraldehyde 3-phosphate dehydrogenase causes

A) the reduction and phosphorylation of glyceraldehyde 3-phosphate to produce 1,3-bisphosphoglycerate.

B) the oxidation of a molecule of NAD+ to NADH.

C) Neither A nor B.

D) Both A and B.

7) A cell that has been fed glucose containing carbon — radioactive with carbon 14 in carbon #1 will have ________ percent of the radioactivity in each mole of glyceraldehyde-3-phosphate.

A) 0%

B) 25%

C) 50%

D) 100%

8) Which of the following enzymatic reactions are control points for glycolysis?

A) Glucose 6-phosphate isomerase.

B) Aldolase.

C) Both A and B.

D) Neither A nor B.

9) Mutases are described as

A) polymerases that catalyze phosphoryl group transfers.

B) isomerases that catalyze the transfer of phosphoryl groups from one part of a substrate molecule to another.

C) forming intermediate free phosphate (Pi).

D) All of the above.

10) Which of the following mutases catalyze the formation of a 2,3-BPG intermediate?

A) Muscle phosphoglycerate mutases.

B) Plant phosphoglycerate mutases.

C) Yeast phosphoglycerate mutases.

D) A and C only.

E) All of the above.

11) Transfer of the phosphoryl group from PEP to ADP is an example of

A) a mutase reaction.

B) isomerization.

C) dehydrogenase.

D) substrate-level phosphorylation.

12) Enzymes that catalyze the same reaction are called ________.

A) isozymes

B) complementary enzymes

C) cofactors

D) catalytes

13) Compared to pyruvate, the carbon atoms in lactate ________.

A) are more reduced

B) are more oxidized

C) are equally as oxidized

D) carry more charge

14) Under what situation might lactic acidosis occur?

A) Lactate dehydrogenase is inactive.

B) Transport of glucose into cells is accelerated.

C) Oxygen supply to tissues is inadequate.

D) PFK-1 is over-activated.

15) Seven of the ten reactions in the glycolytic pathway have free energy values close to zero. What does this tell us about those reactions?

A) They are near equilibrium reactions.

B) They are not control points for pathway regulation.

C) They are reversible reactions.

D) All of the above.

E) None of the above.

16) Some reaction steps in the glycolytic pathway have positive standard free energy changes. Which statements apply?

A) The standard free energy for these steps is not the same as the actual free energy change in cells. The actual free energy change must be negative or zero.

B) The reaction steps with positive standard free energy changes are likely to be regulatory steps for the pathway.

C) The steps with a positive standard free energy change are the fastest steps in the pathway.

D) The steps with a positive standard free energy change must be coupled to an ATP →ADP conversion.

17) Once inside a cell, glucose is rapidly phosphorylated to glucose-6-phosphate. What is the main purpose of this phosphorylation?

A) To keep glucose inside the cell.

B) To form a high-energy compound.

C) To activate PFK-1.

D) To prevent mutarotation.

18) More than one step in the glycolytic pathway is subject to regulation. It might seem most efficient to regulate only the first step of a pathway to avoid buildup of intermediates and to conserve materials and energy. Why is the first step of glycolysis not the only regulated step?

A) Some sugars can enter the glycolytic pathway beyond the first step. If steps other than step one were not regulated, the breakdown of these sugars would be essentially uncontrolled.

B) Having more than one regulated step in the pathway allows for feedback inhibition.

C) Control of a single step in a reaction pathway is difficult because the concentrations of enzymes in cells are very low. It's easier to control more than one enzyme.

D) All the ATP in a cell would be depleted very quickly if only the first step of glycolysis were regulated.

19) PFK-2 and fructose 2,6-bisphosphatase are two names for the same enzyme. The name PFK-2 is used for the enzyme's catalysis of the phosphorylation of fructose 6-phosphate to fructose 2,6-bisphosphate. The name fructose 2,6-bisphosphatase is used for its catalysis of the reverse reaction. What is unique about this enzyme that makes it logical to use two names?

A) It is one of very few enzymes that can catalyze both the forward and reverse reactions.

B) The enzyme is a monomer when catalyzing the phosphorylation reaction and a dimer when catalyzing the reverse reaction.

C) The forward and reverse reactions occur in different compartments within the cell, so a different name is used for each activity.

D) The enzyme is bifunctional. The forward and reverse reactions are catalyzed by different sites on the same enzyme.

20) In the liver, ________ has a main use for maintaining blood glucose, but it can also be used to synthesize glycogen, or enter the pentose phosphate pathway to produce ribose 5-phosphate.

A) glucose-1-phosphate

B) glucose-1,6-bisphosphate

C) fructose-6-phosphate

D) glucose-6-phosphate

21) How does mannose enter the glycolytic pathway?

A) It is converted mannose 6-phosphate and then isomerized to fructose 6-phosphate which enters the pathway.

B) It can enter directly into the first step of glycolysis because hexokinase converts mannose to glucose 6-phosphate.

C) Mannose is first split into two trioses that are directly converted to glyceraldehyde 3-phosphate.

D) Mannose is not metabolized via glycolysis. It enters a separate pathway.

Use the mRNA codon chart to translate this DNA message:

1. List the sequence of amino acids in this chain
2. Suppose the sixth base in the DNA chain was an A instead of a C. How would this affect the protein

            produced?

3. What is the name given to this type of mutation in a protein chain? Explain

Which of the following bird species are most closely related?

       A. Picoides borealis and Phylloscopus borealis

       B. Numenius borealis and Picoides borealis sapiens

      C. Numenius americanus and Grus Americana

      D. Picoides villosus and Picoides borealis

The similarity of the embryos of chickens and humans is evidence of ________.

       A. biochemical similarities

       B. developmental similarities

       C. morphological similarities

       D. biogeography

If the coat of a virus about to attack a bacterium is labeled with radioactive sulfur and the DNA is labeled with

                 radioactive phosphorous, over time

1. both the sulfur and the phosphorous will be found within the bacterium
2. only the sulfur will be found inside the bacterium
3. only the phosphorous will be found inside the bacterium
4. both the sulfur and the phosphorous will be found outside the bacterium

The joining of amino acid 2 to amino acid 3 (letter "D") will be by

. Protein X is a single polypeptide with three functional domains. The first is a globular domain which has a protein binding domain and contains both alpha-helices and beta-sheets. The second domain is a group of seven alpha-helices that contain mostly hydrophobic amino acids. The third domain appears to be an enzymatic domain which transfers a phosphate group from ATP to a hydroxyl group on another protein. Postulate the function of this protein and give reasons that support this prediction.

Please re-order the steps below to accurately represent the events that occur during transcription and translation.

1. mRNA is sent out into the cytoplasm where it will bind with a ribosome

2. Helicase "unzips" DNA by breaking the hydrogen bonds between base pairs

3. The ribosome reads the mRNA 3-letters at a time

4. The tRNA that matches the code brings in the Amino Acids to add to the protein being built

5. RNA Polymerase starts building mRNA from 5' to 3' and replaces Thymine with Uracil

1. All of the following are possible results of excessive protein intake, except ____________

   		Excess protein may become a burdensome on kidneys as they excrete urea.
   		protein can be used to make glucose
   		dehydration
   		excess protein can be stored as fat
   		all of the above are possible results.

1 points   

QUESTION 2

1. The two phases of protein synthesis in the cell are ____________ which takes place in the __________, and ___________ which takes place in the _______________

   		transcription in the nucleus, and translation in the ribosomes.
   		translation in the nucleus, and transcription in ribosomes
   		transcription in the nucleus, and translation in the mitochondria.
   		translation in the nucleus, and transcription in the golgi apparatus.

2 points   

QUESTION 3

1. Proteins are involved in all of the following functions except ___________

   		promoting bowel function
   		making hormones
   		making enzymes
   		aiding in immune function
   		providing cell structure
   		providing energy

1 points   

QUESTION 4

1. Positive Nitrogen balance results when protein intake exceeds its loss. This is expected in all of the following conditions, except _____

   		during pregnancy
   		during growth spurt
   		in athletic training
   		a feverish person with loss of appetite

1 points   

QUESTION 5

1. Which of the following is classified as a complete protein?

   		kidney beans
   		whole-grain bread
   		fat-free milk
   		corn tortillas

1 points   

QUESTION 6

1. Vegetarian (vegan) diet is becoming more popular. All of the following statements are correct, except ________

   		There is a concern about developing vitamin B-12 deficiency as well as zinc and calcium.
   		Vegan diet is often rich in antioxidants, dietary fibers, and phytochemicals.
   		It is possible to get all nutrientional requirements from vegan diet, if planned well
   		A dish made of beans (limited in methionine) and rice (limited in lysine) will supply the body with all essential amino acids.
   		it is important to compensate for deficiencies in vegan diet, Vegans can use fortified food or take supplements
   		all of the above statements are correct regarding vegetarian diet.

1 points   

QUESTION 7

1. For a healthy adult whose weight is 60 kg, total RDA is ___________ per day, and % of daily energy obtained from protein should be __________ respectively.

   		4.8 grams, 8%
   		36 grams, 30%
   		48 grams, 10-35%
   		60 grams, 20-35%

2 points   

QUESTION 8

1. Hemoglobin is a protein that contains 4 polypeptide chains. Its structure is considered _________

   		primary
   		secondary
   		tertiary
   		quaternary

1 points   

QUESTION 9

1. This process involves synthesis of nonessential amino acids, while that process involves making glucose from non-carbohydrate source, respectively

   		transamination, ketogenesis
   		deamination, gluconeogenesis
   		transamination, gluconeogenesis
   		deamination, glycolysis

1 points   

QUESTION 10

1. Marasmus is protein-deficiency malnutrition, while Kwashiorkor is energy-deficit malnutrition

   True

   False

1.The following data were obtained in a study of an enzyme known to follow Michaelis-Menten kinetics:

2/27/ 20

V0 (mol/min)

   217
   325
   433
   488
   647

Substrate added (mmol/L)

0.8 2 4 6 1,000

The Km for
A) 1 mM., B) 1000mM, C) 2mM, D ) 4mM, E) 6mM

this enzyme is approximately:

2. To

1. A) the enzyme concentration.

2. B) the initial velocity of the catalyzed reaction at [S] >> Km.

3. C) the initial velocity of the catalyzed reaction at low [S].

4. D) the Km for the substrate.

5. E) both the enzyme concentration and the initial velocity of the catalyzed reaction at

   [S] >> Km.

3. An enzyme that can convert glucose into fructose is a member of which class of enzymes?

A) Oxidoreductases, B)Transferase, C) Hydrolases, D) Lyases, E) Isomerases

4. Which amino acid is NOT capable using its side chain (R group) to participate in general acid-base catalysis?
A) Asp, B) His, C) Ser, D) Val, E) Lys

calculate the turnover number of an enzyme, you need to know:

5. Treatment of methanol poisoning by using ethanol is an example of what type of enzyme inhibition?
A) mixed inhibition, B) uncompetitive inhibition

C) noncompetitive inhibition D) Competitive inhibition, E) Suicide Inhibition

6. What functional groups are present on this molecule?

A) ether and aldehyde, B) Hydroxyl and Aldehyde, C) Hydroxyl and Carboxylic acid, D) hydroxyl and Ester , E) hydroxyl and ketone

7. Which statement about intrinsically disordered proteins is TRUE?

A) B) C)

D) E)

They contain small hydrophobic cores.
They represent misfolded conformations of cellular proteins.
They have no stable three-dimensional structure and therefore have no cellular function.
They are responsible for proteostasis.
They can interact with multiple protein-binding partners and are central to protein interaction networks.

8.
protein aggregate?

Which disease is NOT one characterized by or associated with an unfolded

A) Alzheimer disease, B) Diabetes, C) Parkinson Disuease
D) Scurvy, E) All of these diseases are linked to unfolded protein aggregates

9. Which amino acid when repeated six to ten times at the N- or C-terminal ends of a protein allows that protein to bind to Ni2+ ions?

a.Glu, b. His, c. Ala, d. Tyr, e. Asp

10. The biochemical activity of a protein, such as its enzymatic activity, is called its _____ function.

a. phenotypic , b. genotypic, c. cellular, d. molecular, e. organismal