Moodle multiple choice questions

Question 1

Which of the following morphological changes is NOT typically seen in a cell that is undergoing apoptosis?

Select one:

a.
The cell rounds up.

b.
The cell swells.

c.
The nuclear envelope disassembles

d.
The nuclear chromatin breaks into fragments.

e.
Large cells break up into membrane-enclosed fragments

Answer 1

The cell swells.

Question 2

Initiator and executioner caspases share all of the following features EXCEPT that …Select one:

a.
they undergo cleavage during activation.

b.
their active form is a dimer.

c.
they are cysteine proteases (they have a cysteine residue at their active site).

d.
they are inhibited by IAPs.

e.
their inactive form is a monomer.

Answer 2

they are inhibited by IAPs.

Question 3

Soon after the discovery of nerve growth factor (NGF), researchers injected newborn mice with rabbit antiserum (i.e. serum that contains antibodies) against NGF. They observed massive nerve cell death compared to appropriate control injections. Up to 99% of the neurons in some parts of the developing peripheral nervous system died after about a week of daily injections. These results suggest that …

Answer 3

developing neurons undergo cell death in the absence of NGF.

Question 4

Apoptotic cells are efficiently phagocytosed by neighboring cells or macrophages. Which of the following DOES NOT normally happen in this process?Select one:

a.
The apoptotic cell loses or inactivates “don’t eat me” signals.

b.
The apoptotic cell rounds up and detaches from its neighbors, which facilitates phagocytosis.

c.
The apoptotic cell releases some of its cytoplasmic content to induce a local inflammatory response.

d.
The apoptotic cell exposes phosphatidylserine at its surface, which interacts with receptor proteins on the surface of phagocytes via “bridging” proteins.

e.
all of the above

Answer 4

The apoptotic cell releases some of its cytoplasmic content to induce a local inflammatory response.

Question 5

Which of these is a pro-apoptotic protein

Select one:

a.
Bcl-xl

b.
Bcl-2

c.
AKT

d.
Bax

e.
IAP

Answer 5

Bax

Question 6

Which proteins form the apoptosome?

Answer 6

Cytochrome c, APAF1, APAF1, Caspase 9

Question 7

The extrinsic and intrinsic pathways are the only ways that apoptosis can be initiated?
True or false

Answer 7

False

Question 8

The marker of apoptosis includeSelect one:

a.
DNA fragmentation

b.
chromatin condensation

c.
all of the above

d.
caspase activation

e.
loss of membrane integrity

Answer 8

all of the above

Question 9

A cell in G0 is said to be in a state of,

Answer 9

quiescence

Question 10

The G1 gap phase creates a control point to ensure a cell:

Answer 10

Is large enough to pass into S phase

Question 11

During mitosis when does nuclear envelope breakdown occur?

Answer 11

Interphase

Question 12

In Rao and Johnsons Cell fusion experiments, which of the following cell fusions had two mitotic nuclei in the resultant cell:

Answer 12

A G2 Cell fused with an M phase cell.

Question 13

In Rao and Johnson’s Cell fusion experiments, which of the following cell fusions resulted in a cell with two replicating nuclei?

Answer 13

a G1 cell fused with an S phase cell

Question 14

DNA replication and centrosome duplication occur during:

Answer 14

interphase

Question 15

The flexibility of a biological membrane is strongly influenced by;

Answer 15

Temperature

Question 16

Based only on the nomenclature of a fatty acid, rank these fatty acids in order of likely melting temperature, from highest to lowest.

1) 12:0

2) 10:3∆4,6,8

3) 12:1∆5

4) 12:3∆5,7,9

5) 20:0

Answer 16

d.
5,1,3,4,2

Question 17

Which of the following amino acids are more likely to be found in the centre of a transmembrane domain of a polytopic integral membrane protein?

Answer 17

Leucine

Question 18

In a lipid bilayer, lipids can theoretically diffuse between the membrane leaflets (termed transbilayer diffusion or “flip-flop”) or diffuse laterally in the same leaflet. Which of the following statements is TRUE?

Answer 18

Lateral movement of lipids is faster than transbilayer movement.

Question 19

Which of the following statements is TRUE of polytopic integral membrane proteins;

1) They are held in place in the membrane by the hydrophobic effect.

2) They can either span the entire length of the hydrophobic part of the lipid bilayer or just one leaflet (one sheet of the bilayer).

3) They are usually soluble in an aqueous environment.

4) They interact with the hydrophobic core of the bilayer via predominantly non-polar amino acids.

5) They can only have one transmembrane section.

6) They are attached to the membrane by covalent attachment to a lipid headgroup.

Answer 19

1 and 4