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WorksheetsCell biology revision 1
Total questions: 28
Worksheet time: 18mins
the site of ribosome production
Nucleolus
Ribosomes
Chloroplast
E.R.
Endoplasmic reticulum membrane which is associated with ribosomes is called_______
ER lumen
Smooth endoplasmic reticulum
Rough endoplasmic reticulum
Endosome
Which of the following is the function of smooth endoplasmic reticulum?
Protein synthesis
Macromolecule digestion
Lipid synthesis and storage
Ribosome production
Which organelle receives proteins, then packages, processes and distributes them?
Endoplasmic Reticulum
Lysosomes
Mitochondria
Golgi bodies
What is the function of a cell membrane?
to control what enters and leaves the cell
to support the cell
to perform different functions in each cell
to form a hard outer covering for the cell
Identify a cholesterol molecule
structure A
structure B
structure C
structure D
If a cell is in an extremely hot environment, what is the function of cholesterol in the plasma membrane?
increase the fluidity of the plasma membrane by preventing crystallisation of the fatty acid tails
the cholesterol will do nothing
decrease the fluidity of the plasma membrane by preventing the phospholipids from moving apart
the cholesterol will increase the fluidity of the plasma membrane by pushing the phospholipids apart
If a cell is in an extremely COLD environment, what is the function of cholesterol in the plasma membrane?
increase the fluidity of the plasma membrane by preventing the crystallisation of the fatty acid tails
nothing
decrease the fluidity of the plasma membrane by holding the phospholipids together
increase the fluidity of the plasma membrane by pushing the phospholipids apart
Which membrane is more viscous/ less fluid?
Polypeptides synthesized at cytosolic ribosomes are destined....
to either remain in the cytosol or be transferred to specific organelles
for the cell membrane
for the extracellular environment
to remain in the ER
The presence of what directs proteins to either the nucleus, mitochondria, chloroplasts, peroxisomes?
an amino group
an organelle specific sequence
a signal recognition particle
a translocon channel
Proteins with an endoplasmic reticulum signal sequence (ERSS) will follow which protein sorting pathway?
secretory
non-secretory
How do proteins destined to follow the secretory pathway cross the ER membrane?
protein passes through a translocon after it is fully translated
by diffusion through a translocon
protein passes through a translocon as it is being translated
protein enters lumen by endocytosis after translation is complete
The ER signal sequence is removed by signal peptidase enzymes after the protein passes through the translocon. This is an example of...
proteolytic cleavage
ubiquitination
phosphorylation
glycosylation
What happens after proteins have entered the lumen of the ER?
Select all that may apply
folded in to final conformation
may be post-translationally modified
may be passed to golgi body for further processing and packaging
may be transferred to mitochondria and used to produce ATP
Identify 2 pathways that can be used to degrade proteins no longer required or damaged
autophagic-lysosomal
ubiquitin-proteasomal
heterotrophic degradation
dehydration synthesis
What might trigger autophagic degradation of proteins?
increased temperature
low blood pressure
starvation
high blood sugar
The name for the very narrow gap between the two cells in a synapse:
synaptic cleft
electrical synapse
chemical synapse
ganglion
A chemical released by exocytosis at terminal axons of a neuron into a synapse to send a signal to another cell:
synaptic vesicle
electrical synapse
neurotransmitter
action potential
At what stage do sodium channels open allowing sodium ions to flood the cell, increasing cell voltage?
Depolarizarion
Repolarization
Hyperpolarization
Resting Potential
At what stage does Potassium channel open allowing the ion to exit the neuron, and Sodium close, slowing/stopping this ion from entering the neuron?
Depolarizarion
Repolarization
Hyperpolarization
Resting Potential
Which one of the following is involved in maintaining a resting membrane potential?
Na+/K+ ATPase pump moves 3Na+ in for every 2K+ out
Na+/K+ ATPase pump moves 3K+ in for every 2Na+ out
Na+/K+ ATPase pump moves 3Na+ out for every 2K+ in
Na+/K+ ATPase pump moves 3K+ out for every 2Na+ in
what is cyclin-dependent kinase (CDK)?
uncontrolled cell growth due to abnormal functioning of cell cycle regulators
an enzyme that controls the cell cycle and is activated by cyclin
a hormone that signals the movement of receptors ot cell surface.
a cyclin enzyme that cannot operate without a kinase attached.
