2014/15

Question 1

The “three domains of life” system

i) claims that all living organisms belong to three groups.
ii) groups Archaea and Bacteria in the group prokaryota.
iii) is based on a comparison of ribosomal protein sequences.
iv) is based on ribosomal RNA sequences.
v) groups plants, animals and fungi in the eukaryota.

Answer 1

i, iv, v

Question 2

Bacterial cells have

i) a cell wall.
ii) a plasma membrane.
iii) a nucleus.
iv) mitochondria.
v) an endomembrane system.

Answer 2

i, ii

Question 3

What is a major advantage of using green fluorescent protein in cell biology?

A. It is cheaper than any other staining method.
B. It allows the observation of protein and organelles in living cells.
C. It is less toxic.
D. It is simply a very cool tool.
E. Its use is recommended by environmental organisations.

Answer 3

b

Question 4

Electron microscopy is suited to visualise

i) individual molecules.
ii) viruses.
iii) organelles.
iv) entire cells.
v) entire organisms.

Answer 4

i, ii, iii

Question 5

According to the “RNA World Hypothesis”, the protocell had which of the following features?

i) It was surrounded by a lipid-bilayer (a biomembrane).
ii) It contained ribozymes and RNA.
iii) It contained several compartments.
iv) It stored information in nuclear DNA.
v) It secreted proteins into the extracellular space.

Answer 5

i, ii

Question 6

The plasma membrane

A. surrounds mitochondria.
B. is part of the membranes of chloroplasts.
C. is another name for the endo-membrane system.
D. is the outer membrane of a cell.
E. is the system of membranes in the cytoplasm.

Answer 6

d

Question 7

Cholesterol has which of the following functions?

i) It serves as an energy storage.
ii) It is the precursor of a vitamin.
iii) It modifies the fluidity of membranes.
iv) It is used to synthesise sex hormones.
v) None of these.

Answer 7

ii, iii, iv

Question 8

Which structures are present in plants but are NOT found in an animal cell?

i) Cell wall.
ii) Chloroplast.
iii) Ribosome.
iv) Mitochondria.
v) Nucleus.

Answer 8

i, ii

Question 9

A polysome

A. is a complex of many ribosomes that simultaneously translate a single mRNA.
B. is a single ribosome translating multiple mRNAs at the same time.
C. is a ribosome consisting of numerous large subunit.
D. is a ribosome complex in mitochondria.
E. is a complex of RNA-polymerase and bacterial ribosomes.

Answer 9

a

Question 10

Protein phosphatases have the following features:

i) They remove phosphate groups from proteins.
ii) They are lipids that take part in the formation of the plasma membrane.
iii) They oppose the activity of kinases.
iv) They “walk” vesicles along the fibres of the cytoskeleton.
v) They include clathrin-receptors in the plasma membrane.

Answer 10

i, iii

Question 11

Packaging of the DNA in metaphase chromosomes involves

A. tubulin.
B. ribosomes.
C. histones.
D. RNA-polymerase. 
E. all of the above.

Answer 11

c

Question 12

Which are the pathways that deliver material to the lysosome for degradation?

i) Autophagy
ii) Phagocytosis
iii) Secretion
iv) Endocytosis
v) Translation

Answer 12

i, ii, iv

Question 13

Exocytosis is

A. the release of material into the extracellular space.
B. the transport of vesicles to the plasma membrane.
C. the cell wall that is surrounding plant cells.
D. a way of signalling extracellular cues to the nucleus.
E. is a crucial step in mitosis.

Answer 13

a

Question 14

Fusion of transport vesicles with a target membrane involves

i) tethering of the vesicles to factors in the target membrane.
ii) exchange of signalling molecules between the vesicles and the membrane .
iii) docking of the vesicles to the target membrane.
iv) signalling to the nucleus.
v) recycling of the vesicles for reuse.

Answer 14

i, iii

Question 15

Which of the following are filaments of the eukaryotic cytoskeleton?

i) Microtubules
ii) F-Actin
iii) Intermediate filaments
iv) Cellulose fibrils
v) ParM filaments

Answer 15

i, ii, iii

Question 16

In the cytoplasm, diffusion is sufficient to distribute

i) nuclei.
ii) transport vesicles.
iii) ATP.
iv) ions.
v) organelles.

Answer 16

iii, iv

Question 17

Microtubules have important roles in

i) lipid storage.
ii) chromosome segregation in mitosis.
iii) cell motility of ciliate protists.
iv) long-distance axonal transport.
v) generating force in cell migration.

Answer 17

ii, iii, iv

Question 18

Primary cilia are

A. the first cilia that an embryo forms.
B. structures that mature into secondary cilia.
C. structures that take part in cellular signaling.
D. structures that are mainly composed of actin-bundles.
E. used by sperm cells to swim.

Answer 18

c

Question 19

Which of the statements listed apply to BOTH cilia and flagella?

i) They contain an axoneme.
ii) They are formed by a basal body.
iii) They rotate due to the activity of a basal rotary motor.
iv) They show ‘intraflagellar transport’.
v) They are surrounded by the plasma membrane.

Answer 19

i, ii, iv, v

Question 20

Hair and nails mainly consist of

A. keratin.
B. kinesin.
C. collagen.
D. cellulose.
E. microtubules.

Answer 20

a

Question 21

Which of the following proteins are microtubule-dependent molecular motors?

A. Kinesin and myosin. 
B. Keratin and dynein. 
C. Dynein and kinesin 
D. Myosin and keratin 
E. Keratin and kinesin

Answer 21

c

Question 22

Apoptosis is a process by which the cell

A. multiplies.
B. splits in two.
C. inherits its DNA.
D. kills itself.
E. communicates with other cells.

Answer 22

d

Question 23

Which of the following applies to molecular motors?

i) They are enzymes that hydrolyse ATP in order to move along the cytoskeleton.
ii) They are enzymes that hydrolyse fatty acids in order to move along the cytoskeleton.
iii) They move cargo (eg membranous organelles or vesicles) through the cell.
iv) They make steps along microtubules or F-actin.
v) They utilise intermediate filaments for long-distance transport of cargo.

Answer 23

i, iii, iv

Question 24

Cell-cell connections in animal epithelial cells serve the following functions:

i) Diffusion of ions and water between cells.
ii) Organization of the actin cytoskeleton.
iii) Limiting diffusion between cells and over the epithelium. iv) Anchoring intermediate filaments.
v) Connecting cells to the extracellular matrix.

Answer 24

i, ii, iii, iv, v

Question 25

Cell division in bacteria is mediated by

A. ParM 
B. FtsZ 
C. MamK 
D. MreB 
E. Mbl

Answer 25

b

Question 26

Mutant moss cells that have no FtsZ protein contain

A. larger nuclei.
B. larger endosomes. C. longer mitochondria. D. longer chloroplasts. E. fewer microtubules.

Answer 26

d

Question 27

Bacterial pili are

A. points of replication of the bacterial genome.
B. sites of chemotropic signalling.
C. dynamic extensions of the cell.
D. cytoskeletal elements in a cell.
E. secreted polysaccharides that help cell motility.

Answer 27

c

Question 28

Which of the following is/are NOT part of the fungal cytoskeleton?

i) Microtubules.
ii) Intermediate filaments.
iii) F-actin.
iv) Molecular motors.
v) ParM filaments.

Answer 28

ii, v

Question 29

Bacterial viruses are called?

A. Enveloped viruses. 
B. Naked viruses.
C. Phages.
D. Plaques.
E. Virions.

Answer 29

c

Question 30

A virus particle can contain which of the following components

i) a capsid.
ii) a membrane coat.
iii) enzymes (e.g. lytic enzymes).
iv) DNA.
v) RNA.

Answer 30

all

Question 31

Chloroplasts are characterised by the following:

i) They are surrounded by a double-membrane.
ii) They contain cristae.
iii) They fix carbon dioxide using NADH and ATP (carbon fixation cycle).
iv) They are the sites of photosynthesis.
v) They are the sites of cell respiration.

Answer 31

i, iii, iv

Question 32

Plasmodesmata are

A. extensions of the cytoplasm that are surrounded by a plasma membrane.
B. pores in the nuclear envelope that mediate nuclear transport.
C. cell-cell contacts in plant cells that mediate exchange between cells.
D. contractile extensions that supports cell movement.
E. aggregates of ribosomes that translate proteins in the cytoplasm.

Answer 32

c

Question 33

Which of the following organelles are bounded by a double membrane?

i) Mitochondria
ii) Nucleus
iii) Peroxisomes
iv) Lysosomes
v) Chloroplasts

Answer 33

i, ii, v

Question 34

In which organelles are proton gradients used to synthesise ATP?

i) Lysosomes
ii) Endosomes
iii) Mitochondria
iv) Peroxisomes
v) Chloroplasts

Answer 34

iii, v

Question 35

Which of the following apply to both mitochondria and chloroplasts?

i) Being bounded by a double membrane.
ii) Having thylakoid membranes.
iii) Having ribosomes.
iv) Having circular DNA.

Answer 35

i, iii, iv

Question 36

Proteins in chloroplasts are encoded by

i) nuclear DNA
ii) chloroplast DNA
iii) mitochondrial DNA

Answer 36

i, ii

Question 37

Which of the following comments regarding viruses is/are TRUE?

i) Viruses have a metabolism.
ii) Viruses are cells
iii) Viruses can be surrounded by a membrane.
iv) Viruses contain RNA or DNA.

Answer 37

iii, iv

Question 38

The fungal “Spitzenkörper” is

A. an accumulation of secretory and endocytic vesicles.
B. a protein complex that helps tethering vesicles.
C. a molecular complex that mediates membrane fusions at the hyphal tip.
D. a cluster of ribosomes that appear dark in electron microscopy.
E. a tip of a mushroom where hyphae concentrate.

Answer 38

a

Question 39

Bacteria move in liquid or over surfaces by which of the following mechanisms?

i) They secrete polysaccharides and glide on them.
ii) They form flagella that rotate and move the cell over surfaces and in liquid.
iii) They form pseudopodia that allows the bacteria to crawl.
iv) They recruit actin from the infected host cell and push themselves through the cytoplasm.
v) They form dynamic protein fibres that are used to pull them over surfaces.

Answer 39

i, ii, iv, v