4.1.1.3 Cell specialisation

How do cells specialise?

By undergoing differentiation

What is differentiation?

A process that involves the cell gaining new subcellular structures in order for it to be suited to its role

What are sperm cells specialised to do?

Carry the male’s DNA to the egg cell for successful reproduction

How are sperm cells specialised?

Streamlined head and long tail to aid swimming, many mitochondria supply the energy to allow the cell to move, the top of the head has digestive enzymes which breaks down outer membrane layers of the egg cell

What are nerve cells specialised to do?

Transmit electrical signals quickly from one place in the body to another

How are nerve cells specialised?

The axon is long which enables the impulses to be carried along long distances, the nerve endings have many mitochondria which supply the energy to make neurotransmitters allowing the impulse to be passed from one cell to another

What are muscle cells specialised to do?

Contract quickly to move bones or to squeeze, causing movement

How are muscle cells specialised?

Special proteins slide over each other which causes the muscle to contract, lots of mitochondria provides energy from respiration for contraction, they store glycogen that’s used in respiration

What are root hair cells specialised to do?

Take up water by osmosis and mineral ions by active transport from the soil as they’re found in the tips of roots

How are root hair cells specialised?

They have a large surface area due to root hairs meaning more water can move in, large permanent vacuole affects movement speed of water from the soil to the cell, mitochondria provides energy for the active transport of mineral ions into the root hair cell

What are xylem cells specialised to do?

Transport water and mineral ions up the plant from the roots to the shoots

How are xylem cells specialised?

A chemical called lignin is deposited when formed which causes the cells to die and become hollow which joins them from end to end to form a continuous tube so water and mineral ions can move through, light is deposited in spirals which helps the cells withstand the pressure from the movement of water

What are phloem cells specialised to do?

Carry the products of photosynthesis to all parts of the plants

How are phloem cells specialised?

Cell walls of each cell form structures called sieve plates when they break down which allows the movement of substances from cell to cell