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KS4 Biology
B13a / Side 1
Structure of the male reproduction system
Label the following diagram:
Complete the following table:
Structure
Function
Testis
Carries sperm from testes to urethra
Scrotum
Coiled tube where sperm is stored
Urethra
Transfers sperm into vagina
Produces fluid containing nutrients for
sperm, makes up semen
Ureter
Produces alkaline fluid to add to sperm to
make semen
1. Why are the testes located outside of the body protected by the scrotal sacs?
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KS4 Biology
B13a / Side 2
2. What is the function of the fluids produced by the prostate gland and seminal
vesicle?
3. Outline the route taken by ejaculated sperm from their site of production to the
oviduct of the female.
4. How does a condom work as a contraceptive?
5. Label the following diagram of a sperm cell:
a) Sperm are extremely adapted to their function; describe in what ways they
have become specialized.
b) How many sperms are needed to fertilize an egg cell?
Sha Tin College
Science Department - June 17
KS4 Biology
B13a / Side 3
Structure of the Female Reproductive system
Label the following diagram of the female reproductive system:
Complete the following table:
Structure
Function
Ovaries
Connect ovaries to uterus, where
fertilization occurs
Uterus
Narrow neck of uterus, dilates during
labor
Vagina
1. The uterus is said to be the most powerful muscle in the body. Why does it need
to be so powerful?
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KS4 Biology
B13a / Side 4
2. What happens to the egg cell once it is released from the ovaries?
3. Fill in the missing words in the following paragraph:
An egg is released by one of the two _______________ approximately every 28
_______________. It passes into the end of the _______________ and moves
slowly downward. If _______________ is to take place the egg must be met by a
_______________ before or just after it reaches the _______________. Sperm
are produced in the tubules of the _______________ in vast quantities.
Ejaculation forces the sperm from the _______________ into the sperm duct and
leaves the body through the _______________. Millions of ejaculated sperm is
deposited into the _______________ from here they make their journey to the egg
cell. Thousands of sperms may reach the egg but only _______________ enters it.
_______________ occurs when the sperm nucleus fuses with the egg nucleus to
form a _______________. This is the moment of conception.
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Science Department - June 17
KS4 Biology
B13b / Side 1
Adolescence
Adolescence or puberty is the transition from a sexually immature child into a
sexually mature adult. The average age for the onset of puberty is 12 – 13 in girls
and 13 – 15 in boys. Hormones control development of sexual characteristics in the
male and female.
Complete the following table; use your textbook for assistance:
Male
Female
Hormone
Site of production
Function of hormone
These two hormones also bring
characteristics) in boys and girls.
about
bodily
changes
(secondary
sexual
List these changes in the table below:
Boys
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Girls
Science Department - June 17
KS4 Biology
B13c / Side 1
Ovulation and the menstrual cycle
One of the changes that occur in girls during puberty is the start of her menstrual
periods.
The length of the cycle varies but on average it occurs about every 28 days. The
diagram below illustrates the events that occur during the menstrual cycle.
Essentially during the menstrual cycle an egg cell is matured and released from one
of the ovaries and the lining of the uterus is thickened to prepare for implantation of
a zygote, a fertilized egg cell.
Use the diagram above and your textbook to help you answer the following questions:
1. Describe what happens during menstruation or a period.
2. What is ovulation and when does it occur during the menstrual cycle?
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Science Department - June 17
KS4 Biology
B13c / Side 2
3. At the same time as the egg is developing the lining of the uterus is becoming
thicker with blood vessels. What is the purpose of this thick lining?
4. What is an empty follicle called?
5. What happens to the egg cell and the uterus if fertilization does not take place?
6. During what days in the menstrual cycle do you think the woman is the most likely
to get pregnant if she has sexual intercourse? Explain your answer?
7. Name the two hormones that play a major role in the menstrual cycle.
8. When females reach the age of about 50 years old ovulation no longer occurs and
menstruation ceases, what is this phase known as?
Sha Tin College
Science Department - June 17
KS4 Biology
B13d / Side 1
1. Complete the missing terms in the boxes using the following words:
Implantation
Ovulation
Fertilization
Cell division
2. Match the correct term with the definitions.
a. Vagina
Embryo sinks into the soft uterus lining
b. Zygote
Release of an egg from one of the ovaries
c. Implantation
A fertilized egg cell
d. Fertilization
Release of semen out of the urethra through the penis
e. Ovulation
Male and female nuclei fuse together
f. Oviduct
Where sperm is deposited during sexual intercourse
g. Ejaculation
Where fertilization takes place
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Science Department - June 17
KS4 Biology
B13e / Side 1
Pregnancy
Following successful implantation of the embryo into the lining of the uterus the
placenta develops. The embryo and the placenta is now called a foetus. The placenta
is a temporary organ that allows the blood systems of the fetus and the mother to
come in close contact without actually mixing.
1. In the above diagram, label the structures and colour the mother’s blood red and
the embryo’s blood blue.
2. One of the main jobs of the placenta is to allow the diffusion of substances
between the foetal and mother’s blood systems and vice versa. Complete the
table below.
Substances diffusing from:
Mother to foetus
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Foetus to mother
Science Department - June 17
KS4 Biology
B13e / Side 2
3. Give two reasons why the maternal and foetal circulations are separated.
Inside of the uterus the foetus is surrounded by a fluid filled membrane.
4. Label the following diagram.
What is the function of structure B in the diagram above?
5. What is the function of the amniotic fluid?
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Science Department - June 17
KS4 Biology
B13f / Side 1
Labour and Birth
Pregnancy lasts between 38 – 40 weeks, at the end of the period the baby is ready to
be born and is about 3 kg in weight and 50 cm length.
There are three stages of labour:
A.
B.
C.
Amnion ruptures and the cervix widens/dilates to a diameter of 10 cm.
Strong powerful contractions of the uterine muscle push the bay out of the
uterus through the cervix and vagina.
The placenta and umbilical cord are expelled after the baby is born, this is
known as the afterbirth.
1. Babies are usually born headfirst. What advantages are there in being born in
this position?
2. Some babies are born under weight even though they are born at the right time.
Suggest factors that can affect the birth weight of the baby.
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Science Department - June 17
KS4 Biology
B13g / Side 1
HIV virus
HIV (human immunodeficiency virus) is a virus that severely damages the immune
system by infecting and destroying certain white blood cells. AIDS (acquired
immunodeficiency syndrome) is the final, life-threatening stage of infection of HIV.
At the end of 2002 it is estimated that 42 million people are living with HIV/AIDS
and 19 million have already died since the beginning of the epidemic in the 1980s.
While there are new and improved treatments for HIV, there is no cure, and because
of the nature of the virus, developing a preventive vaccine is problematic.
1) Go to the following website and take a quiz to test how much you know about the
transmission of HIV.
http://www.unicef.org/voy/learning/learhome.html
Use the following website to help you answer the questions below.
http://w3.whosea.org/hivaids/factsheet.htm
2) List four ways in which HIV is transmitted (spread from person to person)
1.
2.
3.
4.
3) A common misconception amongst students is that HIV can be spread from an
infected person by using the same cutlery or bath as them and that mosquitoes
carry the virus. State some other myths that you have heard about on how HIV
can be spread.
4) Suggest how the spread of HIV can be prevented.
1.
2.
3.
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Science Department - June 17
KS4 Biology
B13h / Side 1
World population of Humans
The population of the world surged from 2.4 billion in 1950 to 6.1 billion 50 years
later. The annual increase is about 94 million people; about 260,000 people are added
to the world population each day. As you see the Human population has been growing
at an alarming rate with birth rates remaining high and death rates falling. Rapid
population growth directly affects the global ecosystem placing a greater demand on
the space needed to sustain large numbers of people.
1. Suggest reasons why the world’s population has been rapidly increasing.
 ___________________________________________________________
 ___________________________________________________________
 ___________________________________________________________
 ___________________________________________________________
2. The population growth rate in developed countries in the United States and
Europe is less than 1% but in developing countries such as India and Nigeria the
rate is more than double. What is the impact of a rapidly growing population in
developing countries such as these?
3. Since 1979 China has enforced a controversial one-child policy in its efforts to
control rapid population growth. Apart from such a stringent family planning
measure, suggest other ways that population growth can be limited.
Sha Tin College
Science Department - June 17
KS4 Biology
B13i / Side 1
Review questions
1. The diagram shows part of the female reproductive system
a. Use an S to mark on the diagram the place where sperm are released during
intercourse and an F to show where fertilization usually occurs.
b. Explain how the structure of a sperm enables it to travel from S to F.
2. A few weeks after fertilization, the fertilized egg becomes an embryo, which is
surrounded by amniotic fluid.
a. Label structure F in the diagram
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Science Department - June 17
KS4 Biology
B13i / Side 2
b. Describe two functions of the amniotic fluid
c. Describe how the oxygen level in the blood of the embryo is maintained.
3. The diagram below shows the relative levels of the two hormones, oestrogen and
hormone Q, during a woman’s menstrual cycle.
a. What effect does the build up of oestrogen have from day 9 to day 14?
b. Name hormone Q
c. Where is hormone Q produced?
d. What would be indicated if high levels of hormone Q continued beyond day
24?
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Science Department - June 17