Cell Differentiation & Specialisation

Question 1

What are the 3 stages of cell differentiation

Answer 1

1. Fertilisation
2. Undifferentiation
3. Specialisations

Question 2

Give two example of specialised cells that can be found in animals

Answer 2

• Nerve Cells
• Muscle Cells
• Sperm cells

Question 3

Give two examples of specialised cells found in plants

Answer 3

• xylem cells
• Phloem cells
• Root hair cells

Question 4

Why do animal cells specialise?

Answer 4

• for repair and replacement

Question 5

Do plant cells retain the ability to differentiate and give reasoning?

Answer 5

Yes: many plant cells do not ever become specialised and so continue to have the ability to differentiate

Question 6

Give two ways nerve cells have adapted for their function and how this helps

Answer 6

1. Long fibre (axon) - to be able to carry messages up and down the body over long distances
2. Fatty (myelin) sheath - the fatty sheath increases the speed of the nerve impulses along the neurone

Question 7

Give two ways a sperm cell has adapted for its function and how this helps

Answer 7

1. Lots of Mitochondria - provide lots of energy for the tail
2. Acrosome - contains enzymes for penetrating egg cell membrane

Question 8

Give two ways muscle cells have adapted for their function and how this helps

Answer 8

1. Lots of mitochondria - provide energy for contraction
2. Glycogen - to store energy
3. Muscle fibres - shorten for muscle contraction

Question 9

Give two ways xylem in plant cells have become specialised and how this helps

Answer 9

1. Xylem vessels are composed of elongated, dead cells - maintains a steady flow of water and nutrients throughout the plant
2. no end walls between adjacent cells - minimises water loss and ensures proper hydration and nutrient supply for growth and development

Question 10

Give two ways phloem in plant cells has become specialised and how this helps

Answer 10

1. Very little cytoplasm - allow more solution through
2. Sieve tube elements (specialised cell) - holes between sieve tube elements called sieve plates help sugars and other nutrients move quickly through the phloem
3. Companion cell - provides energy for transport of sugars

Question 11

Give two ways root hair cells cells have become specialised and how this helps

Answer 11

1. Lots of mitochondria - provide energy for active transport
2. Large surface area - maximised absorption of water and mineral ions