Question

Choose the correct option for each of the following.
[4 marks]

A is the semi-permeable Cell wall Cell membrane B \( \overline{\text { Amoeba in phagocytosis. }} \) Active Passive A cell shrinks when it is placed in a solution. hypertonic hypotonic is an example of passive transport. Exocytosis Diffusion

Answer 1

• Cell membrane is the semi-permeable boundary of both plant and animal cells. It allows only selective materials to pass in and out of the cell. Whereas the cell wall is non-living and is hence freely permeable and allows free movement of molecules in and out of the cell.
  [1 mark]
• Amoeba uses active transport to obtain nutrition. It engulfs the food particle through phagocytosis using energy. That is why it comes under active transport.
  [1 mark]
• A cell shrinks down when placed in a hypertonic solution. This is because of the higher concentration of solute in the solution as compared to the cell. As a result, water moves out of the cell.
  [1 mark]
• Diffusion is an example of passive transport as the movement of molecules takes place across a gradient and does not require energy.
  [1 mark]