2.4 - Mistakes

Question 1

Devise an investigation to determine to effect of pH on the rate of growth of pollen tubes.

Answer 1

Test at least 5 different pH values
Add a sucrose solution
Check results after an hour
Use length/time
Place in a water bath
Repeat and calculate a mean

Question 2

Explain the role of the centrioles in sperm following fertilisation.

Answer 2

Be the source of centrioles in the zygote
So spindle fibres can be made
So zygote can divide by mitosis

Question 3

Explain how meiosis gives rise to genetic variation in gametes.

Answer 3

Independent assortment and crossing over
Independent assortment - Gives rise to different combinations of chromosomes
Crossing over - Swapping of sections of chromosmes

Question 4

If the production of mRNA is inhibited, how will this affect the growth of a pollen tube?

Answer 4

Decrease
Less transcription so less protein produced
Protein is needed for pollen tube growth