Question 1
State two properties of the cell membrane.
Answer
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- Semi permeable/semi permeability;
- Sensitive to change in temperature; and pH;
Question 2.
Outline two precautions taken during collection and observation of live specimens
Answer
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- Collect only the required specimen;
- Immobilize highly mobile animals
Question 3
- What is the formula for calculating linear magnification using a light microscope
- State two functions of centrioles.
Answer
- Magnification = eye piece lens magnification x objective lens magnification
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– Cell division;
– Formation of cilia and flagella;
Question 4
Describe how diffusion gradient affects the rate of diffusion.
Answer
– the greater the diffusion between two points the faster the rate of diffusion;
- Increasing concentration of molecules increases the diffusion gradient;
- Increasing concentration of molecules increases the diffusion gradient;
Question 5
What is a guard cell.
Answer
- Specialised bean shaped cells; mostly found on the lower leaf surface lying close to epidermal cells and contain chloroplasts;