MUTATION 2

Question 1

define the term chromosome mutation

Answer 1

mutation that involves changes to parts or whole chromosome

Question 2

Explain how a neutral mutation might occur

Answer 2

1. if the mutation is in a non coding region of a DNA
2. If it is a silent mutation,although the base triplet changes the amino acid coded for is still the same,so the protein remain unchanged
3. If the mutation causes a change to the structure of protein however the changed characteristics has no advantage or disadvantage

Question 3

Explain how early humans in africa with dark skin had an advantage over those with a mutation of pale skin

Answer 3

• Dark skin has more of the pigment melanin which protects us from UV light.
• However paler skin has less melanin
• The darker skin humans could produce more vitamin D compared to the paler skin humans
• The paler skin have a disadvantage because they would have burned and developed skin cancer.

Question 4

Explain how as early humans migrated to colder climated this was an advantage paler skin

Answer 4

• Paler skin has less melanin.
• However in low light intensity paler skin can produce more Vitamin D compared to those with dark skin
• There this is an advantage to the paler skin as they can survive and pass on the paler skin gene to their offspring however the dark skin would have to find a source of vitamin D like eating fish,seal meat ect inorder to survive and prevent Vitamin D defficient diseases like rickets

Question 5

name foods that are rich in Vitamin D

Answer 5

• eggs
• fish
• seal meat

Question 6

what condition can be caused by a lack of Vitamin D

Answer 6

• rickets
• narrow pelvis in women which leads to difficult during child birth e.g. death of child or mother
• Sufficient Vitamin D can protect us from cancer and heart disease