Biology Cells

Question 1

How are red blood cells specialised?

Answer 1

They have a large surface area, no nucleus, are a biconcave disc shape and contain haemoglobin.

Question 2

How are muscle cells specialised?

Answer 2

They are elongated, can contract and contain many mitochondria.

Question 3

How are sperm cells specialised?

Answer 3

Half the normal number of chromosomes in the nucleus
Many mitochondria
Long tail to swim

Question 4

How are palisade cells specialised?

Answer 4

Regular shape to pack tightly together
Many chloroplasts (contain chlorophyll)

Question 5

What is unique about stem cells?

Answer 5

They can differentiate to become any type of cell

Question 6

True or false: Once cells are specialised, they cannot differentiate into a different type of cell.

Answer 6

True

Question 7

How many chromosomes are there in humans?

Answer 7

46

Question 8

How many chromosomes are there in gametes?

Answer 8

23

Question 9

How many chromosomes are in red blood cells?

Answer 9

0

Question 10

What is the name of the ability to differentiate into any type of cell?

Answer 10

Pluripotency

Question 11

If a cell is made in bone marrow, what can it become?

Answer 11

Only blood

Question 12

What are unspecialised cells in plants called?

Answer 12

Meristems

Question 13

How old can embryonic stem cells be removed?

Answer 13

3-5 days

Question 14

What are the advantages to using embryonic stem cells for scientific purposes?

Answer 14

Can treat diabetes, paralysis and more conditions (completely unspecialised - pluripotent)
Self-renewal at rate 10x adult stem cells
No risk of infection and unlikely to be rejected
Otherwise ‘wasted’ (taken from IVF clinics when excess/unnecessary)
Painless for embryo (not a baby!)

Question 15

What are the disadvantages of using embryonic stem cells for scientific purposes?

Answer 15

Ethical issues (some lunatics consider it murder)
Potentially synthesised, which also opens up ethical issues (make an embryo, why not a whole baby?)
Difficult to procure and manufacture
Untested in detail as of yet (long-term effects unknown; possibility of causing cancer/tumours)
Time-intensive

Question 16

What are the advantages to using adult bone marrow stem cells?

Answer 16

Pre-specialised (less work required)
Can treat leukemia and other blood conditions
No ethical issues
Tried and tested

Question 17

What are the disadvantages of using adult bone marrow stem cells?

Answer 17

Can only give rise to other blood cells
Difficult and painful to remove (requires operation)
Risk of becoming cancer cells or of rejection
Small-scale and donor-dependent
Cell abnormalities common

Question 18

What is mitosis used for?

Answer 18

Growth of tissues in multicellular organisms
Repair of tissues in multicellular organisms
Asexual reproduction in multicellular organisms
Binary fission in unicellular organisms

Question 19

What chromosomal difference do people with Downs and Edward’s syndrome have?

Answer 19

They have 47 chromosomes

Question 20

Order the stages of mitosis.

Answer 20

Prophase, metaphase, anaphase, telophase

Question 21

What happens in prophase?

Answer 21

Replicate, Condense, Centrioles, Spindle:
The chromosomes are replicated and consist of two chromatids each joined by a centromere.
The chromosomes condense, giving a shorter, thicker appearance.
The centriole splits and the parts move to two opposite ends of the cell, a spindle forming between them, made of tubulin.