Cell differentiation and specialisation 4.1.1.3&4

Question 1

What is cell differentiation and how is it different in animals and plants?

Answer 1

• cells differentiate to form different types of cells

- most animal cells differentiate at an early stage but plant cells differentiate throughout their lives.

Question 2

What happens as a cell differentiates?

Answer 2

• it changes shape

- different sub-cellular structures allow it to carry out a certain function

Question 3

How is sperm specialised for reproduction?

Answer 3

• Flagellum (Tail) – propels the sperm towards the egg.
• Nucleus – contains one set of genetic information (23 chromosomes)
• Acrosome – contains enzymes to digest the egg membrane
• Many Mitochondria – release energy needed to swim

Question 4

How are nerves cells specialised for rapid signalling?

Answer 4

• Long – carry signals long distances
• Branched – can connect to lots of other nerve cells
• Sheath – insulates the electrical signal for rapid signalling

Question 5

How are muscle cells specialised for contraction

Answer 5

• Protein fibres – can contract
• Long – there is lots of room for contraction
• Lots of mitochondria – for respiration to release energy needed for contraction

Question 6

How are root hair cells specialised for absorbing water and minerals?

Answer 6

• Large surface area – can absorb more water and minerals

- Lots of mitochondria – for respiration to release energy for the active transport of minerals

Question 7

How is the phloem cell specialised for translocation?

Answer 7

• Arranged end to end – to form a tube for CELL SAP to travel through from the leaves to the rest of the plant for use or storage
• Holes in the end walls – allow cell sap to pass through

Question 8

How is the xylem cell specialised for translocation?

Answer 8

-Arranged end to end – to form a tube for water and mineral
ions to travel through from the roots to the stem and leaves
-Hollow tube with lignin in the cell wall - for strengthen the cell wall and make it waterproof