MINISTRY OF EDUCATION
SECONDARY ENGAGEMENT PROGRAMME
GRADE 11
BIOLOGY
Week 7
Lesson 2 - Worksheet
Topic: Reproduction in humans
Sub-topic: Fertilization and Development of Foetus
Section A: Read questions carefully and then write answers in your workbook.
The figure below shows a foetus just before birth.
1. Refer to the figure above and outline the function of the parts labelled “Placenta” and
“Amnion”
2. Label the umbilical cord in the above diagram AND explain its role in the development
of the foetus.
3. Name the hormone crucial in parturition (birthing). Does the parturition signal originate
from the mother or the foetus?
4. What are the functions of the placenta other than its endocrine function?
5. Define Parturition (birthing) and describe the three (3) stages of parturition.
6. What is the reason for the absence of menstrual cycles during conception or pregnancy?
Section B: Circle the letter which corresponds with your chosen answer.
7. Which hormonal supplementation therapy is the least likely to assist a female that has
difficulties ovulating?
(A) Luteinizing hormone
(B) Follicle-stimulating hormone
(C) progesterone
(D) Oestrogen
8. Which of these promotes the development of the uterus to maintain pregnancy?
(A) progesterone
(B) oestrogen
(C) oxytocin
(D) luteinizing hormone
9. Fertilization occurs in the
(A) uterus.
(B) cervix.
(C) Fallopian tube.
(D) vagina.
10. Fully identical twins develop as a result of
(A) Fertilization of a single egg by a single sperm, this embryo then splits into two
(B) Fertilization of two eggs simultaneously by two different sperms forming two
embryos
(C) Fertilization of two eggs by a single sperm forming two embryos
(D) Fertilization of a single egg by two sperms, this embryo then splits into two
MINISTRY OF EDUCATION
SECONDARY ENGAGEMENT PROGRAMME
GRADE 11
BIOLOGY
Week 7 - Lesson 2
Answer Sheet
Topic: Reproduction in humans
Sub-topic: Fertilization and Development of Foetus
Section A
The figure below shows a foetus just before birth
1. The placenta is the interface between mother and foetus. Functions of the placenta
include gas exchange, metabolic transfer, hormone secretion, and foetal protection.
Towards the end of the pregnancy, the placenta passes on antibodies to protect the baby
after birth. Alcohol, nicotine and other drugs and medicines can cross the placenta and
cause harm to the baby.
Amnion secretes amniotic fluid which protects the foetus by cushioning it from shocks,
prevents the foetus from adhering to the amnion and serves as a transport medium for
nutrients and metabolites.
2. (See Diagram) The umbilical cord allows for the transfer of oxygen and nutrients from
the maternal circulation into foetal circulation while simultaneously removing waste
products from foetal circulation to be eliminated maternally.
3. The hormone is Oxytocin. The signal originates from the placenta and fully developed
foetus which initiates the foetal ejection reflex triggering the release of the hormone,
oxytocin.
4.
The placenta promotes the supply of nutrients and oxygen to the embryo. It also
facilitates the elimination of excretory wastes and carbon dioxide produced by the
embryo. Placenta aids in the transportation of substances to and from the embryo as it is
connected to the embryo through the umbilical cord.
5. Parturition refers to a process of delivering a baby from the uterus to the vagina to the
outside world. There are three stages of Parturition: (1) Dilation – where there are
contractions and the cervix expands to allow for the passage of the baby, (2) Expulsion –
the baby is pushed out through series of contractions and delivered out of the birthing
canal, and (3) Placental where the placenta is delivered.
6. During pregnancy, all the events of the menstrual cycle stop and there is no menstruation.
Menstruation occurs only when the egg that is released is not fertilized. But in pregnancy,
the released egg is fertilized and hence the uterus lining does not shed, instead it
nourishes the foetus. However, a woman may experience uterine bleeding during
pregnancy due to various reasons that is not due to the period.
Section B
7. Answer: C
8. Answer: A
9. Answer: C
10. Answer: A