Biochem 1

1.

1 point

What is Kcat/Km?

enzyme efficiency

maximal reaction velocity

enzyme affinity

substrate concentration at 1/2 maximal velocity

2.

1 point

Which of the following substances would be most useful to give to a patient with an acute stroke?

tPA

heparin

warfarin

thrombin

3.

1 point

Enzymes do not have an optimal pH for function.

True

False

4.

1 point

What is the most important factor in determining the structure of proteins?

amino acid sequence

covalent bonds

hydrophobic interacts

disulfide bonds

5.

1 point

Which of the following increases hemoglobins affinity for oxygen.

increase in pH

binding of one molecule of oxygen

change of Histidine to Serine above the Iron ion (as seen in fetal hemoglobin)

presence of BPG

6.

1 point

Which of the following could indicate a recent heart attack if present in a blood test?

CK-MB

glucose-6-phosphate

CK-BB

troponin

cholesterol

7.

1 point

Feedback inhibition occurs when high concentration of reactants of a specific enzyme slow that enzyme down.

True

False

8.

1 point

Which of the following will increase the rate of enzyme (at least to a point)?

increase amount of substrate

increase temperature

increased product

adding an allosteric inhibiter

9.

1 point

Hemoglobin cannot transport NO due to the presence of aspartate residues.

True

False

10.

1 point

How does aspirin reduce blood clotting?

it irreversibly bind to COX1 thereby "killing" platelets

it prevents platelets from hydrolyzing prothrombin to thrombin

it negatively inhibits COX2 causing the platelet response to be slower

it prevents platelets from being produced by the liver

11.

1 point

What are the main amino acids involved in the action of chymotrypsin?

phenylalanine

histidine

asparagine

valine

serine

12.

1 point

Mutations near the C-terminus of collagen causes a more severe form of osteogenesis imperfecta than at the N terminus.

True

False

13.

1 point

What produces immunoglobulins?

megakaryocytes

hepatocytes

eosinophils

B-lymphocytes

macrophages

14.

1 point

PT is used to measure heparin levels.

True

False

15.

1 point

Where is albumin made?

pancreas

spleen

liver

bone marrow

16.

1 point

What molecule is the main molecular buffer of human blood?

oxygen

bicarbonate ion

chloride ion

carbon dioxide

17.

1 point

Which of the following amino acids would allow for the closest packing of the collagen triple helix?

phenylalanine

glycine

valine

proline

18.

1 point

Which of the following disease(s) is/are from misfolded proteins (prions)?

De Vivo disease

kuru

Alzheimer's disease

Creutfeldt-Jakob disease

19.

1 point

Which vitamin is important in making clotting factors?

A

K

D

E

20.

1 point

What factor is changed in the presence of a noncompetitive inhibiter?

Vmax

Kcat

Km

no change

21.

1 point

What is the purpose of the distal histidine on the hemoglobin molecule?

prevent arsenic from inhibiting oxygen binding

it serves no important purpose

prevent CO from bind with the Iron

prevent BPG from binding more tightly and preventing oxygen transport

22.

1 point

Adding sulfates to sugars makes them more hydrophilic

True

False

23.

1 point

What molecule dissolves blood clots once healing has begun?

alpha-1-anti-trypsin

heparin

von Willibrand factor

tissue plasminogen activator

24.

1 point

Which of the following amino acids is not involved in the formation of glycoproteins?

C

S

T

HyLys

N

25.

1 point

A single nucleotide polymorphism (SNP) will always result in coding for a new amino acid.

True

False

26.

1 point

How does alpha1-antitrypsin prevent emphysema?

it allows elastase to protect the lung alveoli from degredation

it prevents elastase from breaking down the elastin-rich alveoli

it prevents trypsin from breaking down the elastin-rich alveoli

it causes emphysema

27.

1 point

What level or levels of protein structure do disulfide bonds contribute to?

primary

secondary

tertiary

quaternary

28.

1 point

Which of the following structures has a negative feedback to the coagulation cascade?

von Willebrand factor

activated protein C

vitamin K

ADP

29.

1 point

What type of enzyme are most proteases?

lyases

hydrolases

kinases

ligases

30.

1 point

In what peak are a majority of immunoglobulins found relative to albumin?

alpha 2

alpha 1

beta

gamma

31.

1 point

When one molecule of oxygen bind to hemoglobin, it makes it easier for other molecules of oxygen to bind.

True

False

32.

1 point

Which of the following enzymes are activated by trypsin?

chymotrypsinogen

proeleastase

prolipase

procarboxypeptidase

33.

1 point

Enzymes stabilize the transition state of a reaction.

True

False

34.

1 point

The variable region of immunoglobulins binds to antigens.

True

False

35.

1 point

Cross links of what amino acid gives elastin its elasticity?

W

K

Q

R

36.

1 point

Between which two amino acids does trypsin cleave?

K

N

R

E

D

L

37.

1 point

How long before surgery should a patient stop taking their aspirin (for blood thinning)?

10 days

7 days

3 days

1 day

38.

1 point

What is the purpose of an enzyme?

lower the activation energy

lower the total free energy required for the reaction

change delta G to a positive value

change delta G to a negative value

39.

1 point

In keratin, where would a majority of the R groups of the amino acids be?

pointing out from the alpha helix

forming hydrogen bonds with each other

clumped in sets of 4 subunits

anti-parallel to each other on a flat surface

40.

1 point

Hexokinase and glucokinase are:

isozymes

zymogens

only present in the brain

phosphotases

41.

1 point

Which of the following cells give rise to platelets?

T cells

megakaryocytes

neutrophils

monocytes

B cells

42.

1 point

Which coagulation factor allow fibrin to cross link?

factor Xa

factor XIIIa

thrombin

factor VIIIa

43.

1 point

What coenzyme is derived form vitamin B6?

FAD

pyridoxal phosphate (PLP)

NAD

coenzyme A (CoA)

44.

1 point

Which of the following amino acids would be most likely to form hydrogen bonds?

V

L

G

T

45.

1 point

When you get your flu vaccination, what are the first immunoglobulins made?

IgM

IgE

IgA

IgD

IgG

46.

1 point

What molecule is not formed properly in Ehlers-Danlos syndrome?

pyruvate dehydrogenase

collagen

heme

keratin

47.

1 point

If a child is allergic to peanut butter, what immunoglobulins would be most prevalent when the child is exposed to that allergen?

IgE

IgA

IgG

IgM

IgD

48.

1 point

Which of the following are only competitive inhibiters?

statins

ACE inhibiters

lead

aspirin

CO

49.

1 point

Which of the following are examples of secondary protein structures?

alpha helix

beta sheet

delta cube

gamma sphere

50.

1 point

How does fibrin get activated?

prothrombin activates latent fibrin

thrombin cleaves fibrinogen into fibrin

endothelial cells produce antithrombin III

factor X activates fibrinogen