Question 3
- Name the parts labelled I, II, III, IV, V and VI. [3 marks]
- Mention three substances that are transported from the blood of the mother to the embryo. [3 marks]
The diagram below illustrated a foetus developing in the uterus of a human. Study it and answer questions 3(a), 3(b) and 3(c).
- List four venereal diseases that could affect the embryo before birth. [4 marks]
Observation
This question was attempted by majority of the candidates and their performance was poor.
In part (a) majority of the candidates did not do well in it. In part (b) many candidates could not mention substances that are transported from the blood of the mother to embryo. In part (c) they did fairly well in it.
The expected answers are as follow:
(a) LABELLED PARTS OF DIAGRAM
I - umbilical cord
II - embryo/foetus
III - amnion
IV - cervix
V - amniotic fluid
VI - placenta
(b) SUBSTANCES TRANSPORTED FROM THE MOTHER’S BLOOD TO THE EMBRYO
- oxygen
- vitamins
- minerals/named
- digested food materials/named
- water
- antibodies
(c) VENEREAL DISEASES THAT COULD AFFECT EMBRYO BEFORE BIRTH
- syphilis
- gonorrhea
- chancroid
- lymphogranuloma venereum
- granuloma inguinale/genitalwarts
- HIV/AIDS