Question 1
Membranes are found within and surrounding cells.
Which option is not a role of membranes in cells?
acts as a barrier between areas
cell signalling
provides support for cell
site of chemical reactions
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Question 2
Which statement defines active transport?
movement of large molecules through the cell-surface membrane into the cytoplasm of a cell
movement of molecules or ions from where they are in a low concentration to where they are in a higher concentration
movement of molecules or ions from where they are in a high concentration to where they are in a lower concentration
net movement of water molecules across a partially permeable membrane from a region of higher water potential to one of lower water potential
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Question 3
The diagram represents the fluid mosaic model of membrane structure.
Which two components contribute to the fluidity of the membrane?
1 and 3
2 and 4
3 and 5
4 and 6
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Question 4
What happens to an animal cell when it is placed in a solution with a more negative water potential?
it loses solutes to the solution and swells
it loses water by osmosis and shrinks
it takes in solutes and swells
it takes in water by osmosis and bursts
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Question 5
Which adaptation would increase active transport of carbohydrates from a plant cell?
areas where the cell wall is thin
increased permeability of the cell wall
large surface area of the cell-surface membrane
selective permeability of the vacuole membrane
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Question 6
Which molecules in cell-surface membranes contribute to cell recognition?
cholesterol, glycolipids, phospholipids
cholesterol, phospholipids, proteins
glycolipids, glycoproteins, proteins
phospholipids, glycoproteins, proteins
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Question 7
Which substances can pass directly through cell-surface membranes without using a carrier protein or channel protein?
1 - CO2
2 - Ca2+ and Na+
3 - H2O
1 and 2
1 and 3
2 and 3
2 only
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Question 8
The cells in the roots of beetroot plants contain a red pigment. When pieces of root tissue are soaked in cold water, some red pigment leaks out of the cells into the water. The higher the temperature of the water, the higher the rate of loss of red pigment from the cells.
Which statement(s) could explain this trend?
1 - enzymes in the cells denature as the temperature increases, so pigment cannot be used for reactions in the cells and diffuses out
2 - as the temperature increases, the tertiary structure of protein molecules in the cell-surface membrane changes, increasing the permeability of the membrane
3 - phospholipid molecules gain kinetic energy as temperature rises, increasing the fluidity of the phospholipid bilayer and allowing pigment molecules to diffuse out more easily
1 and 2
2 and 3
2 only
3 only
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Question 9
What describes a carrier protein in cell-surface membranes?
a glycoprotein that is found on the outer surface of the membranes allowing cell recognition
a glycoprotein that is involved in moving substances through the membranes by both active and passive transport
a protein that allows the attachment of signalling molecules which brings about changes within the cell
a protein that is involved in moving substances through the membranes by passive transport through water-filled pores
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Question 10
Which statements about endocytosis are correct?
1 - it is part of phagocytosis
2 - it is a passive process
3 - materials are taken into the cell
4 - vesicles form within the cytoplasm
1, 2, and 3
1, 2, and 4
1, 3, and 4
2, 3, and 4
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Question 11
When red blood cells are put into pure water they burst (haemolysis).
Which statements explain this haemolysis?
1 - the water potential of the surrounding liquid is lower than the water potential of the contents of the red blood cells
2 - the cell-surface membranes of red blood cells are not supported by cell walls
3 - more water moves into the red blood cells by osmosis than leaves the cells
4 - water enters the red blood cells by osmosis but does not leave the cells
1 and 3
1 and 4
2 and 3
2 and 4
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Question 12
Four agar blocks are stained green using universal indicator and suspended in 1 mol dm-3 hydrochloric acid.
The time taken for the agar blocks to change from green to red was recorded.
Which agar block would be the first to become completely red?
2 cm x 2 cm x 2 cm
2 cm x 1 cm x 4 cm
2 cm x 3 cm x 2 cm
5 cm x 2 cm x 3 cm
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