HARD
AS and A Level
IMPORTANT
Earn 100
The fact that the surface area to volume ratio decreases with the increasing size is also true for whole organisms. Explain the relevance of this for transport systems within organisms.
Important Questions on Cell Membranes and Transport
MEDIUM
AS and A Level
IMPORTANT
In Figure 'b', the system has come into equilibrium, so there is no net movement of water molecules. What can you say about the water potentials of the two solutions A and B?
EASY
AS and A Level
IMPORTANT
Why can plasmolysis not take place in animal cells?
HARD
AS and A Level
IMPORTANT
There are more mitochondria than average in pancreatic acinar cells. Suggest a reason for this.
EASY
AS and A Level
IMPORTANT
What are the most abundant molecules in the cell surface membranes of plant cells?
EASY
AS and A Level
IMPORTANT
Where are the carbohydrate portions of glycolipid and glycoproteins located in the cell surface membrane?
EASY
AS and A Level
IMPORTANT
In a signalling pathway, which of the following types of protein acts as a switch to release a second messenger?
EASY
AS and A Level
IMPORTANT
One role of cholesterol in membranes is
HARD
AS and A Level
IMPORTANT
Describe fully what will occur if a plant cell is placed in a solution that has a higher water potential than the cell.
Use the following terms in your answer:
(cell wall, freely permeable, partially permeable, cell surface membrane, vacuole, tonoplast, cytoplasm, water potential, turgid, osmosis, protoplast, equilibrium)
