Chapter 4: Circulatory and respiratory systems

Human reproduction

Chapter overview

2 weeks

After looking at several of the organ systems within the human body in overview in Chapter 2, the next three chapters will now look at some of these systems in more detail.

This chapter on "Human reproduction" starts off by looking at the purpose of reproduction and how humans mature during puberty in order to be able to reproduce. This will be very relevant to your learners as they are in this stage in their lives at the moment.

Be aware that learners might not feel comfortable discussing reproduction in the classroom, and older teens might laugh or make inappropriate jokes to conceal their own discomfort.

Some tips for when teaching human reproduction:

Respect your learners' questions and concerns. Some of them may not have had an opportunity before to ask questions about reproduction, especially if their parents did not feel comfortable discussing this with them. This is a sensitive topic, and learners might be embarrassed to ask questions. Encourage your learners to ask questions and not be embarrassed. Learners must be told to phrase their questions carefully and to use scientific words, with no vulgar expressions. You yourself, as the teacher, must only use scientific terms.
Discuss processes openly so that learners are comfortable within the classroom environment to talk and learn about reproduction and how it influences their lives. Discourage and discipline any laughing or disrespectful behavior from other students.
Possibly bring in a guest speaker. Learners might feel more comfortable asking a stranger questions. Also, if you bring in an expert, such as a gynecologist or midwife, learners might take the subject more seriously.
If necessary, you can separate boys and girls. For example, if you are showing a graphic video about the female reproductive organs, it might be useful to have the boys watch a similar video in another room that explains the male reproductive organs.
Avoid portraying the reproductive system in a negative light or as "forbidden" as this will only add to some of the discomfort that learners might already feel. At this stage in their lives, learners are already very interested in reproduction and the changes that their bodies are going through. This is natural and should be embraced so that they are educated and can make informed choices about their sexual health going forward.
Here is a website to do some further reading: http://ezinearticles.com/?Teaching-Teens-About-the-Reproductive-System&id=1471773

3.1 Purpose and puberty (2 hours)

Tasks	Skills	Recommendation
Activity: Reflecting on population growth	Identifying, predicting, writing	Optional

3.2 Reproductive organs (1 hour)

Tasks	Skills	Recommendation
Activity: Identify the role of the male and female bodies in reproduction	Identifying, writing	Suggested
Activity: Identify structure and function	Identifying, describing, explaining, writing	CAPS suggested
Activity: Comparing the reproductive organs	Comparing, summarising, writing	Suggested

3.3 Stages of reproduction (3 hours)

Tasks	Skills	Recommendation
Activity: Flow diagram of the pathway of sperm	Summarising, describing	CAPS suggested
Activity: Comparing fertilisation and menstruation	Comparing, summarising, drawing	Suggested
Activity: Debate Surrogacy	Working in groups, discussing, debating, presenting, writing	CAPS suggested
Activity: Describing different contraceptives	Identifying, describing	Optional
Activity: Forum discussion	Working in groups, discussing, debating, presenting, writing	Optional

What is puberty and what does it mean when we "reach puberty"?
Why do we all go through puberty at different times and rates?
What changes take place inside our bodies during puberty?
What do our reproductive organs look like when they are mature?
How does reproduction occur?
What is menstruation and why does it occur once a month?
How does a baby grow inside a woman's uterus?
Are there ways to prevent pregnancy and the transmission of STDs?

At this stage in your life, your body is probably going through all sorts of changes as it grows, develops and matures. In this chapter we will learn more about these changes and why they occur.

Purpose and puberty

birth control
conception
fertilisation
implantation
population growth rate
puberty
sexual intercourse
sperm

The purpose of reproduction

You have previously learnt that reproduction is one of the seven life processes, and like all organisms, humans need to reproduce to ensure the survival of the species.

You can use this section to open up discussion about population growth and population control. At the end of the chapter there is a debate regarding contraceptives but teachers may choose to include a discussion on the different ethical points of view regarding contraceptives at this point already.

Video on our world population growth.

Reflecting on population growth

An interesting suggestion if you have an internet connection and a projector or smartboard to display a website, is to open up the link provided here in the visit box on our "Breathing Earth". This simulation very clearly shows how our population is growing. You can open up the link at the start of the lesson and leave it running for the duration. Then at the end of the lesson, you can see how much the population of the world has grown during your one lesson. Alternatively, if you do not have an internet connection in your classroom, ask some of your learners to take out their mobile phones and go to the site. Even if you only have a few mobile phones within the classroom, you can get learners to each take a look at the site at the start and end of the lesson. Do not be afraid to embrace the technology that your learners are using on a daily basis! They most likely have their cellphones in their pockets in class anyway, unless they have been banned during school hours.

A simulation to show population growth http://www.breathingearth.net/

Have a look at the website link provided in the visit box about our "Breathing Earth". This will give you an idea about how our population is growing.

In 2011 the world's population grew to 7 billion people, one billion more since 1999. Medical advances and increases in agricultural production (food) allow more and more people to live longer lives.

In ancient times, countries such as India, Rome and Greece, saw a large population as a source of power. The Romans even made laws about how many babies a couple could have and punished those who did not follow the rules. Yet Confucius (551-478 BC) thought that too many people was a problem, as there wouldn't be enough food to feed everyone, leading to war and famine and various other problems. Today in China this philosophy still applies and couples are only allowed one baby and are heavily taxed if they have more than one.

South Africa's population grew by 15,5%, or almost 7-million people, in the space of 10 years to reach a total of 51.7-million in 2011. This is according to the country's latest national census which took place in 2011. The last census took place 10 years previously in 2001.

QUESTIONS:

These questions are meant to stimulate discussion within your class. You can go through these as a class or learners can then do them individually and then discuss their answers.

List any possible reasons why you think South Africa would want to have a large population.

Learner-dependent answer. Might include: more people so more manpower and more taxes; might include religious or cultural bias; etc.

What are some advantages and disadvantages to the country in which the number of children per couple is limited so that the population growth is limited?

Advantages: lower population growth; lower pressure on the country's resources; lower drain on resources, particularly on the education resources; higher standard of living for families

Disadvantages: fewer people to pay taxes; religious or cultural non-compliance might lead to revolt

Predict what possible long-term problems might arise if the population in South Africa continues to grow at the fast rate at which it is currently growing.

With fewer resources to go around many might starve and since they might not have work or social grants to support them. Unemployment would increase even more. This might also lead to increased crime as people try to provide for themselves and their children, as well as drug and alcohol abuse as a coping mechanism.

Have a look at the following diagram which shows the percentage growth a country's population in a year. The different colours give an indication of the growth rate, as shown in the key. For example, countries which are colour coded yellow, have an annual growth rate of 3%. This means their population increase by 3% each year. Answer the questions which follow.

http://commons.wikimedia.org/wiki/File:Population\_growth\_rate\_world\_2005-2010\_UN.PNG — Percentage growth rate of each country. http://commons.wikimedia.org/wiki/File:Population_growth_rate_world_2005-2010_UN.PNG

Which continent would you say has the largest percentage growth rate each year? Justify your answer.

Africa has the largest population growth rate. This can be seen as it has the largest number of countries which are coloured green and yellow which shows the highest annual percentage growth rate.

Many countries in Europe are coloured light purple in the diagram. What does this mean?

Learners need to look at the legend to see that light purple means a growth rate of "

Various population control methods are put in place around the world - contraceptives to stop women from falling pregnant, abortion clinics, large tax incentives to convince people not to want more children, and others. What is your opinion about population control methods and do you think they should be allowed in modern society?

Learner-dependent answer.

The science of overpopulation (video).

What is the purpose of puberty?

hormone
menstrual cycle
oestrogen
penis
testes
testosterone
uterus

The human body is geared towards reproduction to ensure the survival of the species. Men have to produce sperm and ensure that they come into contact with a female egg cell. Women have to produce (and store) egg cells that can be fertilised by a male sperm cell.

Children's bodies and sexual organs are not mature and cannot yet perform the reproductive function. Puberty is therefore the time when a child's body develops and changes. The sexual organs mature to enable the body to produce sex cells. These sex cells are called gametes.

How does puberty just "start"?

Puberty is the stage in the life cycle of humans when we become capable of sexual reproduction. Girls and boys do not, generally, go through puberty at exactly the same time. So how does puberty "start"?

Many of the complex actions that take place in our bodies are controlled by chemical messengers called hormones. Hormones are produced by different glands in our bodies. The pituitary gland is an important gland which controls most of the body's hormones and hormonal activities. It is about the size of a pea and located at the base of the brain.

This animation shows the position of the pituitary gland (the pink gland) http://upload.wikimedia.org/wikipedia/commons/9/9c/Rotating_brain_colored.gif

Puberty is brought on when the pituitary gland releases specific hormones into the bloodstream. These hormones then travel to the immature sex organs and signal the hormones in these to be released.

In girls, the ovaries are stimulated by hormones released by the pituitary gland to release the hormone oestrogen. In males, the testes are stimulated to release the hormone testosterone. These hormones initiate all the bodily changes that you experience during puberty.

What changes during puberty?

The main purpose of puberty is for the sexual organs to mature. However, the hormones which are released from the reproductive organs also start a number of other changes in the human body. We call these secondary sexual characteristics.

Visit this interactive site to explore the changes that occur during puberty http://www.bbc.co.uk/science/humanbody/body/interactives/lifecycle/teenagers/

Puberty brings about the following secondary changes in females:

Breasts start to develop that may be used for breastfeeding a baby after childbirth.
Pubic hair starts to grow at the onset of puberty. Underarm hair also starts to grow.
Menstruation occurs in girls in a monthly cycle once they reach puberty.
Body shape also changes due to the rising levels of oestrogen in the body.
Body odour and acne develop as more oil is secreted and the smell of sweat in the body changes.

At the start of puberty boys are, on average, 2 cm shorter than girls, yet adult men are approximately 13 cm taller than adult women. Puberty brings about the following secondary changes in males' bodies:

Testicle and penis size increases.
Hair starts to grow on the pubic areas, the limbs, chest and the face.
Voice becomes deeper as the larynx (voice box in your throat) grows.
Body shape changes occur as the skeletal muscle and bones increase in size and shape.
Body odour and acne start to develop, as with females.

Let's take a look at the reproductive organs.

Reproductive organs

ejaculate
erection
foreskin
scrotum
semen
vagina
sperm duct (vas deferens)

Let's take a closer look at the male and female reproductive organs to see how they are structured and what functions they perform.

Identify the role of the male and female bodies in reproduction

In the space below, explain what you think the role of the male and female bodies are in reproduction.

The male body has to ...

The male body has to produce sperm and deliver this sperm to the female body in order for it to come into contact with the female egg (ovum).

The female body has to...

The female body has to produce ova (egg cells). Once a month, one egg cell is released and if a sperm cell penetrates the outer layer of the egg cell, fertilisation can take place. This may then lead to pregnancy and the female body adapts to provide for all the needs of the unborn baby before giving birth.

As you learn about the reproductive organs,think carefully about theirstructure and how their structure is adapted to their function.

Male reproductive organs

The male reproductive organs include:

1. Testes and scrotum

Males are born with their two testes hanging outside their bodies. The testes in young boys do not produce sperm. During puberty the two testes release testosterone which then triggers the production of sperm.

Testes is plural and testis is singular.

Up until the 17th century, scientists believed that a tiny, fully formed human being called ahomunculus was passed from the father into the mother's womb during sexual intercourse and grew in size in the mother's womb.

The two testes are each contained in a pouch of skin called the scrotum. The scrotum ensures that the testes are kept at a constant temperature of 35°C which is the temperature at which sperm is produced.

Semen contains sperm cells, dissolved nutrients and enzymes that nourish and protect the sperm inside the woman's body. Every millilitre of semen can contain up to 100 million sperm cells!

2. Sperm duct (vas deferens)

Different tubes (ducts) carry the semen from the testes to the penis. The sperm duct carries the sperm from the testes to the urethra in the penis.

3. The penis

The penis is the external sex organ. The head is often covered by a loose fold of skin called the foreskin. The penis needs to be erect (stiff and hard) to be able to go into the vagina to deliver the sperm to the cervix during ejaculation.

Some cultures have the foreskin removed, which is called circumcision. This may be done when the boy is a baby or later, at puberty.

4. Urethra

The semen moves through the urethra to the outside during ejaculation. The urine passes through the urethra during urination, but the semen and urine do not move through the urethra at the same time.

Identify structure and function

Study the diagram of the male reproductive system. Label each part using its correct scientific name.
In the table, identify the function(s) of the male reproductive organs mentioned.
In the last column, suggest how you think the structure of the organ is adapted to perform the function most effectively.

This question starts to delve into the relationship of structures that are adapted to function. Learners need to LINK structure to function when examining any organ. This is an extension activity and requires learners to apply the knowledge they have just learnt.

Reproductive Organ

Function

Adaptation

Penis

Testes and scrotum

Reproductive Organ	Function	Adaptation
Penis	During sexual intercourse, the penis becomes erect and delivers the sperm into the cervix of the vagina.	The penis is on the outside of the male body, and it is elongated so that it can insert into the vagina and deliver the sperm into cervix. The penis contains the urethra and becomes erect so that it can insert into the vagina.
Testes and scrotum	The testes produce the sperm and the scrotum hold the testes outside of the body.	The testes need to be at 35 oC, which is lower than body temperature, in order to produce sperm. The testes are therefore outside of the male body and hang in the scrotum, which can adjust the temperature of the testes so that the right temperature is maintained in order to produce sperm.

Female reproductive organs

cervix
Fallopian tube (oviduct)
ovary
ovulation
womb

The plural of ovum is ova.

The female reproductive organs include:

1. Vagina

The vagina is a tube that connects the uterus with the outside of the body. During intercourse the vagina acts as a canal for the penis to fit into to deliver sperm. Once a month, during menstruation, the menstrual blood leaves the body through the vagina. It is also the birth canal during childbirth when it stretches to allow the baby to pass through.

2. Uterus

The uterus is hollow with extremely strong muscular walls that can carry and protect a baby. Two oviducts (Fallopian tubes) at the top of the uterus, connect it to the ovaries. The bottom neck of the uterus is called the cervix, which is tightly closed to protect the inside of the uterus.

3. Ovaries

There are two ovaries on either side of the uterus. They produce oestrogen and contain the ova. Each month the ovaries take turns to produce a mature ovum. This is called ovulation.

Women are born with thousands of immature egg cells in each ovary, but very few ever reach maturity.

4. Oviducts (Fallopian tubes)

The uterus and ovaries are connected through a pair of muscular tubes called the oviducts or Fallopian tubes. The mature ovum travels into these tubes to the uterus. Fertilisation occurs in the oviduct.

Learn more about the female reproductive system at this site: http://kidshealth.org/teen/interactive/female_it.html#cat20129

Comparing the reproductive organs

Explain how the structures of the vagina, cervix and uterus are specially adapted to fulfil their functions.

The vagina is elastic and muscular so it can contain the penis during intercourse to prevent the sperm from running out. The cervix is situated at the top of the vagina approximately where the penis' ejaculated sperm will be. It is tightly closed to protect the uterus. It carries the sperm into the uterus which has a thick, blood-rich lining, ready for the implantation of the fertilised egg.

Provide at least 2 reasons why the uterus needs to have strong muscular walls.

The uterus needs to protect and carry the unborn child during pregnancy and it needs to contract and push out the baby during childbirth.

Compare the position and functions of the ovaries with that of the testes. Create a table to show these differences.

A possible table that learners might produce:

Differences between the female ovaries and the male testes

Characteristic	Ovaries	Testes
Position	Inside the body	Outside the body
Hormones produced	Oestrogen	Testosterone
When gametes are produced	Females are born with ova in their ovaries which mature once puberty is reached	Males only start to produce sperm once they reach puberty
Number of gametes released/produced	Release one ovum per month	Produce thousands of sperm daily
Hormone influence	Hormones in the ovaries stimulate the ovum which are already present so that they mature	Only start to produce sperm under the influence of the hormones

Stages of reproduction

contraception
contraction
embryo
gestation (pregnancy)
labour
menopause
surrogacy
umbilical cord
zygote

We have already mentioned most of the processes that take place during reproduction. These processes occur in stages. Let's first have a look at the female reproductive cycle.

The reproductive cycle

The female reproductive cycle repeats every 28-30 days to release an egg cell to be fertilised if sperm are present. This cycle will repeat for many years from puberty to menopause (when the reproductive cycle comes to an end).

The processes that occur will differ depending on whether the ovum is fertilised or not. After ovulation, if fertilisation does not occur, the reproductive organs 'reset' through menstruation to start the process again.

Ovulation

Once a month, one of the ovaries releases one mature ovum into the oviduct.. This process is called ovulation. At the same time the uterus wall thickens and develops extra blood vessels. This is in preparation for the possible implantation of a fertilised egg.

There are times in the menstruation cycle near to ovulation when there is a high chance of becoming pregnant. All girls need to be aware of where they are in their own menstrual cycle as each cycle differs slightly.

Learn how to create an ovulation calendar to keep track of a menstrual cycle.

Menstruation

When there is no fertilised egg cell (zygote) to implant in the uterus, the thick layer of blood and tissue is no longer needed. It is passed out through the vagina during menstruation. The entire process is called the menstrual cycle and it normally repeats every 28-30 days.

Learn more about the menstrual cycle: http://kidshealth.org/teen/interactive/female_it.html#cat20129

Fertilisation

During sexual intercourse the erect male penis enters the female vagina. This is called copulation.

The male penis deposits sperm into the female vagina through ejaculation. There can be millions of sperm cells in one ejaculation, but only one will be able to penetrate the outer membrane of the ovum.

After ejaculation into the vagina, the sperm swim into the cervix and through the uterus to the oviducts. Once inside the oviducts, the sperm swim to meet the mature egg that was released from the ovaries and is now traveling towards the uterus.

One sperm cell burrows into the surface of the ovum. Only the sperm's head enters, the tail stays outside. As soon as one has penetrated the outer layer, the surface of the ovum changes and no more sperm will be allowed to enter.

This process is called fertilisation and it takes place in the outer part of the oviduct, and not in the uterus or vagina.

Once the sperm on the right has entered the outer layer of the ovum, no more sperm will be able to penetrate.

Flow diagram of the pathway of sperm

INSTRUCTIONS:

Use a flow chart to track the progress of a sperm cell from the testes in the male body to the ovum in the female body.
Use the space below to draw your flow diagram. Remember to draw arrows.
Use the following terms in your flow chart, in the correct order.
Cervix
Uterus
Urethra
Penis
Testes
Sperm duct
Oviduct/Fallopian Tube
Vagina

The following flow chart can be used as a reference for learners' flow charts:

Video on fertilisation and early development.

Comparing fertilisation and menstruation

INSTRUCTIONS:

Use the following diagram to compare what happens when an egg is fertilised compared to when it is not fertilised. You can even use coloured pens if you have.
Use labels and arrows to illustrate on the left hand side what happens to the ovum if it is fertilised by a sperm cell.

Use arrows and labels to illustrate on the right hand side what happens if the ovum is not fertilised and the woman subsequently menstruates.

Learner-dependent answer

The following diagram shows an example of something that the learners might produce. Learners might battle to do this. A suggestion is to produce a sketch on the board and go through it with them, filling in the annotations. Do not simply draw it up and get learners to copy down the answers. Ask for their input and possibly get different learners to come up to the board to draw in different stages.

Pregnancy and birth

Pregnancy begins the moment the female egg cell is fertilised by the male sperm cell. This is then called a zygote.

This video shows the development of a baby from fertilisation to birth

The zygote will then start to divide and grow as it moves down the oviduct. It will then implant in the uterus lining, where it will continue to grow. The fertilised egg is now called an embryo and undergoes cell division over and over again. This forms a cluster of cells with the different cells differentiating to become the specialised cells, tissues and organs that make up the human body.

An 8-cell human embryo on day 3 after fertilisation.

Where the embryo implants into the spongy, blood-vessel rich lining of the uterus, some of the cluster of cells that formed after fertilisation form the placenta. The placenta is partly formed by the mother and partly by the embryo. The embryo develops an umbilical cord to attach itself to the placenta. The embryo can receive food and oxygen and remove its wastes through the umbilical cord and placenta.

The foetus is attached to the placenta by the umbilical cord.

Video on fertilisation and early pregnancy.

In humans, pregnancy is about 40 weeks (9 months). We call this the gestation period. Towards the end of the pregnancy, the uterus starts to contract. This pushes the head of the foetus into the vagina (birth canal). After the head has appeared the rest of the body comes out quite quickly. The last to come out is the placenta.

Debate Surrogacy

This is an optional activity, depending on your class.

Many couples, for various reasons, are unable to fall pregnant. A surrogate mother can be impregnated with the couple's fertilised embryos and can therefore carry the couple's baby to full term. South African law only allows certain individuals to do this, it is not just available to anybody.

INSTRUCTIONS:

Work in groups of 6.
Debate the issue of surrogacy in your group. Base your debate on the ethical concerns below or any others you may think of.
Appoint a spokesperson for the group.
Each of the groups' spokesperson must then share their groups points of view with the class.
Debate these issues in the class.

There are many ethical issues concerning surrogacy:

In many cases, the surrogate mother is paid to grow the baby inside her body. Often it is women who are poor that agree to be surrogate mothers and it is suggested that people who pay them to carry their babies are exploiting them. Should women be paid to be pregnant and deliver babies?
In certain religions, surrogacy (including the donation of sperm and ova) is seen as "highly immoral" because it involves the intrusion of a third person on a couple's relationship. Should religious institutions be allowed to prevent surrogacy in this way?

Use the following lines to write down some notes on any other points your group discusses:

Learner-dependent answer

Influences on the unborn baby

During pregnancy, what the mother eats, drinks and takes into her body has been shown to directly affect the unborn child. Other substances like smoking, alcohol and drugs have a negative influence on an unborn baby.

Hearing is one of the first senses to develop in a foetus. So it is thought that unborn babies can hear and are affected by sounds whilst in the womb.

The placenta transports nutrients and oxygen to the foetus, and removes metabolic waste products and carbon dioxide. However, it cannot differentiate between nutrients and harmful products, such as nicotine, alcohol or drugs. If the mother uses these substances during pregnancy, they will most likely pass through the placenta to the foetus causing great harm to the unborn child.

Pregnant mothers who drink alcohol during pregnancy may cause irreversible birth defects in their unborn babies. This is called Foetal Alcohol Syndrome.

The University of Stellenbosch has a website on FAS http://www.sancawc.co.za/master/article.php?id=14.

Prevention of pregnancy and contraceptives

Anyone who is sexually active and who wants to prevent an unwanted or unplanned pregnancy can take certain precautions.

'Contra-' means against, so 'contra-ception' means against conception.

There are a range of different contraceptives that can be used to prevent pregnancy. There are four different types of contraceptives:

barrier - physically prevent sperm from reaching uterus
hormonal -prevent ovulation and fertilisation in the female using hormones
intra-uterine devices- prevent the embryo implanting
sterilisation - by surgery in men and women which is permanent and not reversible

Describing different contraceptives

It may be possible to get examples of these different types of contraceptives for the learners to have a look at. Many clinics will have samples that can be used for educational purposes. They are normally very willing to hand out stock that has passed its expiry date and is only to be used for educational purposes.

INSTRUCTIONS:

In the following table, several different types of contraceptives have been listed, along with a picture and description.
You need to read the information, look at the images and classify the types of contraceptive as one of the following:
barrier
hormonal
intra-uterine device
sterilisation

Contraceptive	Description	Classification
Male condoms	These thin sheaths of rubber are placed over the erect penis before inserting it into the vagina. When the male ejaculates the sperm and seminal fluid is caught in the condom and cannot enter the cervix.
Diaphragm	The diaphragm is a small rubber cap that is placed at the entrance to the uterus before sexual intercourse to create a seal and prevent sperm from entering the uterus.
Tubal ligation in women	A surgical procedure in women in which the the oviducts are cut and tied which prevents mature eggs from reaching the uterus for fertilisation.
Oral contraceptive pill	Often referred to as "the Pill", it is taken every day by mouth. It contains a combination of female hormones which prevents ovulation each month.
Female intra-uterine device (IUD)	A small 'T'-shaped device is inserted into the uterus and prevent fertilisation. It is a long-acting, reversible contraception as the device may be removed again. It is not suitable for women who have not yet had a baby and must be inserted by a doctor.
Vasectomy	A surgical procedure in males in which the vas deferens is cut and tied. Sperm are therefore prevented from becoming part of the ejaculate.

Contra ce ptive	Description	Classification
Male condoms	These thin sheaths of rubber are placed over the erect penis before inserting it into the vagina. When the male ejaculates the sperm and seminal fluid is caught in the condom and cannot enter the cervix.	Barrier
Diaphragm	The diaphragm is a small rubber cap that is placed at the entrance to the uterus before sexual intercourse to create a seal and prevent sperm from entering the uterus.	Barrier
Tubal ligation in women	A surgical procedure in women in which the the oviducts are cut and tied which prevents mature eggs from reaching the uterus for fertilisation.	Sterilisation
Oral contraceptive pill	Often referred to as "the Pill", it is taken every day by mouth. It contains a combination of female hormones which prevents ovulation each month.	Hormonal
Female intra-uterine device (IUD)	A small 'T'-shaped device is inserted into the uterus and prevent fertilisation. It is a long-acting, reversible contraception as the device may be removed again. It is not suitable for women who have not yet had a baby and must be inserted by a doctor.	Intra-uterine device
Vasectomy	A surgical procedure in males in which the vas deferens is cut and tied. Sperm are therefore prevented from becoming part of the ejaculate.	Sterilisation

Some intra-uterine devices can also be classified as hormonal as they contain progesterone. The progesterone also prevents fertilisation, by increasing the cervical mucous, suppressing the endometrium and sometimes also inhibiting ovulation. The IUDs with copper are non-hormonal and also prevent fertilisation as the copper acts as a natural spermicide within the uterus.

Sexual intercourse with many different partners is very risky behaviour as there are many diseases that are transmitted through the fluids involved in the sexual act. We call these Sexually Transmitted Diseases (STDs). There are many different STDs, for example; HIV/AIDS, Herpes virus, Syphilis, Gonorrhoea and genital warts.

Being faithful to one partner limits your chances of contracting STDs. If you know that your partner has an STD he or she can either get medical treatment for this and/or you can take the necessary precautions to prevent contracting the disease. One of the most popular precautions to prevent the transmission of STDs is for the male partner to wear a condom. However, condoms can break and this can expose you to an STD, so you still have to be careful.

Need to know more about STDs? http://www.cdc.gov/std/general/default.htm [link]or http://kidshealth.org/teen/sexual_health/

Choices regarding unwanted pregnancies

Many women who become pregnant might feel that they do not want or cannot care sufficiently for their unborn baby. Some may feel that they do not have the money to support another baby if they already have other children. When teenage girls become pregnant, many might feel that they would still like to complete their schooling and could not also raise a child. Other women might not want the baby as it might possibly be a result of rape or incest. Many women have many different reasons why they do not want to be pregnant or raise a child.

There are of course various choices that they can make in such a situation.

Adoption - where the baby is given to another family who want to adopt him or her.
Leaving the baby in a place of safety while remaining anonymous. The baby will then be put forward for adoption.
Parenting - keeping the baby with the support of the extended family.
Abortion - terminating the pregnancy by removing the embryo from the mother's uterus.

The following activity will require learners to do some research and interviews and then come back into class to hold a forum discussion. A suggestion is to get learners to start doing some research and thinking about the topics in the days leading up to this lesson. Below is some more information on each of the types of choices a woman is faced with when she experiences an unwanted pregnancy. Read through this first so that you are familiar with the choices before the lesson so that you can help learners with their forum discussions.

Adoption: Many couples in South Africa cannot have children of their own for different reasons and therefore choose to adopt children as their own. There are different organisations that help pregnant mothers who want to give their unborn children up for adoption. The Department of Social Services also helps pregnant mothers in the process of adoption. Adoptive parents typically have to go through a very strict screening process to make sure that they will be fit to raise a young child. When a mother (and where possible the father) signs that their baby will be given up for adoption, they have 60 days in which to change their minds before the adoption goes through. During this time, the baby will be placed in special foster care facilities or with foster families who will care for him or her until they can go to their adoptive parents.

Leaving the baby in a place of safety: Sometimes the parents of a newborn baby, for various reasons, want to get rid of the baby. As a result, many babies are found abandoned. Many organisations in South Africa are trying to provide a safe haven for unwanted babies. One way they approach this, is to provide a baby-safe drop off site where the mother and/or father can place their unwanted baby in a special window with a safety flap on the outside. However, this option has many legal complications. Legally, the babies cannot easily be adopted because they do not often have birth certificates. Since the parents usually cannot be found, they cannot sign adoption papers. Although social workers will try and find the parents to get them to sign the adoption papers, after a few months they may put the baby forward for adoption without the parents' signatures. The best option is therefore to go to a social worker and ask them to help organise the adoption. This also protects the rights of the child.

Parenting: Often when a woman (or teenage girl) realises that she is pregnant, many thoughts rush through her head. If it is an unwanted or unplanned pregnancy she is often filled with feelings of panic, anxiety and fear for the future - for her and her unborn child. She may fear that her parents or partner will abandon her and that she will then be on her own and will have to care for the baby on her own. However, if she is able to talk to her parents and partner, they may be able to find a solution to the situation that will enable her to keep her baby. She may be able to raise her child with the help of her or her partner's extended family. The most important thing is to face her fear and discuss the situation to reach a suitable decision.

Abortion: Some women choose to have an abortion to end their pregnancies. During an abortion, the developing embryo is removed from the mother's womb. Chemical or physical processes can be used, depending on the age of the embryo. Abortions can be risky, especially if they are performed by untrained, unqualified abortionists. During an abortion the mother may lose a lot of blood. Her cervix may also be damaged or torn, or the uterus itself may be damaged during the procedure. These complications are not common when the abortion is performed by properly trained and qualified doctors and nurses in a clean, sterile medical facility. However, sometimes pregnant woman go to places where unqualified or untrained people perform the abortions. They are typically performed in unclean, unhygienic conditions by people without the proper medical training to know what to do in case of an emergency. Complications are very common here, with many of the woman experiencing infections due to the dirty, unsterilised equipment. If someone is considering an abortion, it is therefore very important that they go to a professional abortion clinic that meets very high medical standards of cleanliness and well-trained staff. They should also speak to a caring professional first, as aborting a child may have long term effects, like feelings of guilt.

Forum discussion

This activity relates to Life Orientation. This activity was specifically included at the end of the section to allow for research to occur before the forum discussion. Break the class up into groups of 6 and allow them to move into different areas of the classroom, or perhaps even move outside if space permits. Each group must then conduct their forum discussion according to the instructions and guidelines below.

You, the teacher, can spend a little time with each group to make sure they are on track and discussing the topic. Use the notes provided on the different options for an unwanted pregnancy if you need to provide a group with some background information or some guidelines about what to discuss. Encourage learners to express their points of view and why they believe something.

An alternative is to have one discussion forum in the front of the class and give different learners the chance to sit up front on the panel, and you can be the moderator.

This activity does not need to be assessed and is more for personal education, and a chance for learners to practise debating.

Hold a forum discussion regarding the choices women have when they do not want to be pregnant or raise a child. Before the discussion, do research and interviews with your parents or caregivers, with health professionals or ask your Life Orientation teacher.

How to hold a forum discussion:

In a forum discussion, experts are asked to sit on a panel and give their opinion about a particular topic. There are specific roles in a forum discussion:

Moderator: This person keeps the discussion focused and on track.
Participants: The experts. This will be you, the learners, after you have conducted your research.

Work in groups of 6.
Choose a moderator.
Discuss the different choices that women have regarding unwanted pregnancies using the information you obtained from the interviews you conducted.

Rules for a forum discussion:

The speakers need to take turns to give their opinions.
Treat everyone with dignity and respect. Speak politely.
Use the correct scientific terminology.

Record your findings:

Use the space below to record the findings from the forum discussion explaining what choices women have when faced with an unwanted pregnancy.

Learner-dependent answer

Summary

The main aim of human reproduction is to produce babies to continue the species.
In human reproduction, two gametes (the sperm and egg cell) fuse during conception to form a zygote, that will eventually become a new baby.
Puberty is the stage in the human life cycle when the sexual organs mature and prepare for reproduction.
The pituitary gland below the brain releases hormones that stimulate the testes and ovaries to release hormones that will start the production of sperm in the male and the maturation of ova (egg cells) in the female.
- In males, the hormone testosterone stimulates the testes to produce sperm.
- In females, the hormone oestrogen stimulates the ovaries to produce mature ova.
Testosterone and oestrogen cause different secondary changes in the body.
- Females begin to menstruate, grow breasts and grow pubic and underarm hair, and may experience acne.
- Males grow hair on the pubic area, on the face, chest and underarms, develop a deep voice and may develop acne.
The male reproductive organs are: penis, sperm duct (vas deferens), testes, scrotum and urethra. Sperm is produced in the testes.
The female reproductive organs are: vagina, cervix, uterus, oviducts (Fallopian tubes) and the ovaries. Ova are produced in the ovaries.
Stages in the reproductive cycle include: ovulation → copulation → fertilisation → embryo implants in uterus → results in pregnancy → gestation lasts 40 weeks → childbirth
Pregnancy can be prevented by using contraceptives. Condoms prevent the sperm from reaching the ovum and also prevent the spread of STDs.
Pregnant women have various options if they do not want to keep their babies. Very early in the pregnancy they can undergo an abortion. They may also give the baby up for adoption.

Concept map

This concept map shows all that we have learned about reproduction in humans. Complete it by filling in the blank spaces. You might find this quite tricky, but you need to learn to "read" a concept map by constructing sentences. For example, "Human reproduction can take place once sexual organs are mature. They mature during puberty which is initiated by ….............. The …............ releases hormones which stimulate the ovaries and testes." What is this gland which initiates puberty and releases hormones, and which hormones do the ovaries and testes release? Fill this in below.

Teacher's version

Help your learners to fill in the blanks by asking questions such as, "How often does ovulation occur?" (It occurs once per month).

Revision Questions

Explain the changes that occur to the male and female body during puberty. [10 marks]

For females, these include: breasts develop, pubic hair starts to grow, underarm hair grows, body shape changes, ovaries mature, acne develops in some individuals. For males, these include: penis grows and becomes larger, testes mature, pubic hair starts to grow, facial hair grows, underarm, chest and back hair grows, voice deepens, acne develops in some individuals.

Describe the hormonal control of the start of puberty. Name the organs involved and the hormones. [5 marks]

At the onset of puberty, hormones are released into the blood (these hormones were not specifically named at this level). These hormones travel in the blood and stimulate the reproductive organs. In females, the ovaries are stimulated to produce oestrogen and in males, the testes are stimulated to produce testosterone.

At what stage of the reproductive cycle can one say that a woman is pregnant? [1 mark]

When the egg has been fertilised by a sperm (ie fertilisation), the woman is now pregnant.

There is a urban legend or myth that says that a girl cannot fall pregnant the first time she has sexual intercourse. Think carefully about everything you have learnt about conception and fertilisation, and discuss whether this myth is true or false. [2 marks]

It can be true if the girl has sex before her reproductive organs have matured and therefore before she is able to ovulate. In this instance she will not be able to fall pregnant. If the woman's reproductive organs have matured and she has started to menstruate and ovulate, then she can fall pregnant after sexual intercourse, even if it is the first time. Thus in this instance the myth is not true.

Explain why you think it is important for someone who considers becoming sexually active to know how reproduction occurs in humans. [1 mark]

Learners need to indicate that once someone knows the facts about conception they will be able to take (realistic) precautions to avoid unwanted pregnancies and disease. The will also not believe all the myths and make sensible decisions.

Imagine someone who has many sexual partners asks you for advice on which contraceptive to use. What advice would you give them? [3 marks]

Someone who has many sexual partners stands a high risk of contracting an STD. To prevent this and to prevent an unwanted pregnancy learners should be able to say that they should use a condom during intercourse. They could also possibly suggest that the person limits the number of sexual partners that they have, and if they are in a relationship, then both of them should remain faithful to one partner. Alternatively, if they do continue with many partners, the person should try establish the status of these partners before intercourse, and still use a condom. The person should also be advised to have regular check ups to know their status.

Some people have religious reasons for not using contraceptives. Decide whether you agree with them or not and why. Write a short letter to the editor of local newspaper expressing your concerns about contraceptives from this specific point of view. [6 marks]

Learner-dependent answer

Learners should be able to see the different points of view regarding this issue and reference the debate on this topic that was held earlier in this chapter. There is no right answer, rather the focus should be on the fact that learners can justify their opinions and express themselves. They should draw on this and write their letter in this frame of reference. NB: Learners are not criticizing anyone's religion or culture in this activity.

Do you think schools should teach learners about different contraceptives? Why do you say so? [3 marks]

Learner-dependent answer. Check that learners are able to justify their answer and provide a reason for what they think.

During pregnancy the pregnant mother needs to take care of herself in order to provide a healthy and safe environment for the unborn child. Your local clinic has asked you to produce a brochure that they can display in their waiting room for first-time mothers. Write a detailed list of instructions for a pregnant woman explaining what she needs to do to keep herself and her unborn baby healthy. You can chose how you want to do this - perhaps a list of "Do's" and "Dont's", or else provide some headings under which you can list some instructions such as "Diet" , "Lifestyle", etc. [6 marks]

Learners should refer to the diet and lifestyle choices of the pregnant mother, specifically noting that pregnant mothers who consume drugs and alcohol, also pass these on to the unborn baby through the placenta, resulting in irreversible damage to the unborn child. The mother should therefore avoid these during pregnancy.

this last question does not need to be assessed.

Total [37 marks]

Chapter 2: Systems in the human body

Table of Contents

Chapter 4: Circulatory and respiratory systems