DP Biology (last assessment 2024)
Question 18M.3.HL.TZ1.4b
| Date | May 2018 | Marks available | [Maximum mark: 2] | Reference code | 18M.3.HL.TZ1.4b |
| Level | HL | Paper | 3 | Time zone | TZ1 |
| Command term | Explain | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 2]
18M.3.HL.TZ1.4b
(b)
Explain the causes of spina bifida in vertebrates.
[2]
Markscheme
a. spine/spinal cord does not form properly
OR
incomplete closure of embryonic neural tube/ tissues around the neural tube do not fuse
b. lack of folic acid/folate (B9 vitamin) in pregnancy
c. genetic/family history
d. exposure to certain medication/environmental conditions during pregnancy
