• Different types of cells carry out specific functions and when all cells combine their functions, they can share out the processes of life.
• Each cell is dependent on the other and all of them function collaboratively to support the diverse processes in an organism
• When cells are specialised they carry particular job and develop a distinct shape. The changes in shape enable the cell to carry out its special function.

 

1. Red blood cell (erythrocytes)

• Its function is to transport oxygen from lungs to body tissues and carbon dioxide from body tissue to the lungs.
• Lacks a nucleus to increases surface area for absorption of oxygen.
• Their bi-concave shape and flexibility allow them to pass along small capillaries.
• Contains haemoglobin (red pigment) which carries oxygen needed for cell respiration to produce energy.

 

2. Muscle cell

• It is responsible for contraction when stimulated by a nerve so that movement occurs.
• They are long and thin and have the ability to change their shape when they contract.
• Have large numbers of mitochondria to provide energy for muscle contraction.

 

3. Palisade cell

• Its function is to make food by photosynthesis.
• Packed with chloroplasts that contain chlorophyll for absorption of light.
• They are columnar and closely packed to increase surface area for absorption of sunlight and carbon dioxide.

 

4. Root hair cell

• Responsible for absorption of water and salts from the soil.
• Have thin cell walls to allow water and nutrients to pass easily from the soil
• They are numerous to increase surface area for absorption of water and mineral salts as they are in close contact with the soil.
• The hair like projection on each cell penetrates between the soil particles and offers a large absorbing surface area.
• Large vacuole facilitates water absorption and storage.