The Reproductive The Reproductive SystemSystem

What do I need to know?What do I need to know?

The structure and function of the The structure and function of the parts of the male and female parts of the male and female reproductive systemreproductive system

The Menstrual CycleThe Menstrual Cycle Sexual IntercourseSexual Intercourse FertilisationFertilisation Pregnancy Pregnancy Birth – including growth of the babyBirth – including growth of the baby Contraception MethodsContraception Methods

The male reproductive The male reproductive systemsystem

The male The male reproductioreproduction system n system produces produces and and delivers the delivers the male male gamete gamete (sperm)(sperm)

Seminal Vesicle

Sperm Duct

Side view

The Male Reproductive The Male Reproductive SystemSystemTestisTestis

The testis (Testes) makes spermThe testis (Testes) makes sperm They start to make sperm between They start to make sperm between

the ages of 12 and 14 – Pubertythe ages of 12 and 14 – Puberty Sperm are the male sex cells (also Sperm are the male sex cells (also

called gametes)called gametes) Each sperm cell is tiny and they are Each sperm cell is tiny and they are

produced in large numbers by the produced in large numbers by the testes.testes.

ScrotumScrotum

The scrotum is a sac in which the The scrotum is a sac in which the testes are heldtestes are held

The scrotum allows the testes to be The scrotum allows the testes to be kept at a temperature just below kept at a temperature just below body temperature – this allows body temperature – this allows sperms to be made successfullysperms to be made successfully

Sperm DuctsSperm Ducts

Two sperm ducts carry sperm from Two sperm ducts carry sperm from the testes to the penisthe testes to the penis

A number of glands are located A number of glands are located beside the sperm ductsbeside the sperm ducts

These glands produce a liquid called These glands produce a liquid called seminal fluid seminal fluid in which sperm are in which sperm are releasedreleased

The combination of sperm and The combination of sperm and seminal fluid is called seminal fluid is called semensemen

PenisPenis

The sperm ducts join to form a tube The sperm ducts join to form a tube called the called the urethraurethra

Sperm pass through this tube, which Sperm pass through this tube, which is located in the centre of the penisis located in the centre of the penis

The penis allows semen (or sperm) The penis allows semen (or sperm) to pass out of the male body and into to pass out of the male body and into the body of the femalethe body of the female

The female The female reproductive systemreproductive system

The female The female reproduction reproduction system system produces the produces the female gamete female gamete (egg) and (egg) and protects the protects the developing developing embryo / foetusembryo / foetus

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OvaryOvary The ovaries produce eggsThe ovaries produce eggs The ovaries start to make eggs at The ovaries start to make eggs at

pubertypuberty Eggs are the female sex cells or gametesEggs are the female sex cells or gametes Each egg is larger than a sperm cellEach egg is larger than a sperm cell Normally one egg is formed each month Normally one egg is formed each month

in the female body from puberty until in the female body from puberty until about 50 years of ageabout 50 years of age

At this stage, called the Menopause, the At this stage, called the Menopause, the female stops forming eggsfemale stops forming eggs

Fallopian Tube & UterusFallopian Tube & Uterus

The fallopian tube collects the egg from The fallopian tube collects the egg from the ovary and carries it to the uterusthe ovary and carries it to the uterus

If sperm are present one of them may If sperm are present one of them may join with the egg in the fallopian tube.join with the egg in the fallopian tube.

If there are no sperm present the egg If there are no sperm present the egg diesdies

UTERUSUTERUS The uterus or womb is the area in The uterus or womb is the area in

which a baby (or embryo) will developwhich a baby (or embryo) will develop

Cervix & VaginaCervix & Vagina

The cervix is the opening or the neck The cervix is the opening or the neck of the uterusof the uterus

Sperm pass through the cervix in Sperm pass through the cervix in order to reach an eggorder to reach an egg

VaginaVagina The vagina is a muscular tube into The vagina is a muscular tube into

which thewhich the penis releases spermpenis releases sperm It forms the birth canal when the baby It forms the birth canal when the baby

passes down the vagina at childbirthpasses down the vagina at childbirth

The menstrual cycleThe menstrual cycle

28 day cycle in the 28 day cycle in the femalefemale

Controlled by Controlled by chemicals called chemicals called hormoneshormones

An egg is produced, An egg is produced, and the womb develops and the womb develops a thick lining of blood a thick lining of blood vessels to be prepared vessels to be prepared for pregnancyfor pregnancy

If the egg is not If the egg is not fertilised, the lining fertilised, the lining leaves the womb – leaves the womb – menstruation – and the menstruation – and the cycle begins againcycle begins again

link to animation

Stages in the menstrual Stages in the menstrual cyclecycle

28 day cycle28 day cycle

Approx. daysApprox. days

1 - 51 - 5 Menstruation – loss of uterus Menstruation – loss of uterus lining and unfertilised egglining and unfertilised egg

5 - 135 - 13 Repair of uterus liningRepair of uterus lining

1414 Release of egg from ovaryRelease of egg from ovary

14 - 2814 - 28 Build up of lining of uterusBuild up of lining of uterus

Days 1 - 5Days 1 - 5

The lining of the uterus (which had The lining of the uterus (which had built up during the previous built up during the previous menstrual cycle) breaks down.menstrual cycle) breaks down.

This lining along with some blood, is This lining along with some blood, is passed out of the body through the passed out of the body through the vaginavagina

This process is called This process is called menstruationmenstruation or having a periodor having a period

During these days an egg matures in During these days an egg matures in the ovarythe ovary

Days 6 - 13Days 6 - 13

A new lining develops in the uterusA new lining develops in the uterus The lining will be needed to nourish The lining will be needed to nourish

a developing baby if the female a developing baby if the female becomes pregnantbecomes pregnant

The egg continues to develop in the The egg continues to develop in the ovaryovary

Day 14Day 14

The egg is released from the ovaryThe egg is released from the ovary This is called This is called ovulationovulation The egg can survive for two days The egg can survive for two days

in the fallopian tubein the fallopian tube Ovulation Ovulation is the release of an egg is the release of an egg

from the ovaryfrom the ovary

Day 15 - 28Day 15 - 28

The lining of the uterus remains in The lining of the uterus remains in place until it breaks down on the place until it breaks down on the first day of the next menstrual cyclefirst day of the next menstrual cycle

The Fertile PeriodThe Fertile Period The fertile period is the days in the The fertile period is the days in the

menstrual cycle when a female is most menstrual cycle when a female is most likely to become pregnant if she has likely to become pregnant if she has intercourseintercourse

Sperm can stay alive in the female Sperm can stay alive in the female reproductive system for up to reproductive system for up to three daysthree days - - this means that pregnancy can occur if the this means that pregnancy can occur if the female has intercourse 3 days before female has intercourse 3 days before ovulationovulation

The egg can stay alive for The egg can stay alive for 2 days after 2 days after ovulationovulation – this means that pregnancy – this means that pregnancy can occur if the female has intercourse 2 can occur if the female has intercourse 2 days after ovulationdays after ovulation

This means that the fertile period This means that the fertile period lasts from day 11 to day 16 in a lasts from day 11 to day 16 in a typical menstrual cycletypical menstrual cycle

Menstrual cycles can be longer or Menstrual cycles can be longer or shorter in different females – the shorter in different females – the fertile period is different for every fertile period is different for every femalefemale

In some cycles the fertile period In some cycles the fertile period could start as early as day 8 or 9, could start as early as day 8 or 9, while in other cycles it could last while in other cycles it could last until day 18 or beyonduntil day 18 or beyond

Sexual intercourseSexual intercourseThe natural process of The natural process of

transferring the transferring the sperm from the sperm from the body of a male to body of a male to the body of a femalethe body of a female

Millions of sperm are Millions of sperm are transferred in a fluid transferred in a fluid called semen…they called semen…they immediately begin immediately begin swimming towards swimming towards the single egg cellthe single egg cell

Occurs when a male gamete Occurs when a male gamete (sperm) fuses with the female (sperm) fuses with the female gamete (egg) to form a zygotegamete (egg) to form a zygote

Also referred to as conceptionAlso referred to as conception SPERM +EGG = ZYGOTESPERM +EGG = ZYGOTE

Sperm + egg = zygote

FertilisationFertilisation

Path of the SpermPath of the Sperm

Normally over 100 million sperm are Normally over 100 million sperm are released into the vaginareleased into the vagina

The sperm swim through the cervix The sperm swim through the cervix and into the uterusand into the uterus

They can swim from the uterus They can swim from the uterus towards the fallopian tubetowards the fallopian tube

If there is no egg present in the If there is no egg present in the fallopian tube the sperm die within fallopian tube the sperm die within three daysthree days

Fertilisation usually happens in the Fertilisation usually happens in the oviduct / fallopian tubeoviduct / fallopian tube

A fertilised egg – zygote - may then move A fertilised egg – zygote - may then move down into the wall of the uterus / wombdown into the wall of the uterus / womb

FertilisationFertilisation

PregnancyPregnancy a zygote undergoes a zygote undergoes

cell division and cell division and develops within the develops within the womb into a foetuswomb into a foetus

over 40 weeks the over 40 weeks the foetus develops all foetus develops all its human featuresits human features

It develops inside a It develops inside a protective sac of protective sac of fluidfluid

It receives food via It receives food via a blood supply in a blood supply in the placentathe placenta

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BirthBirthAfter about 40 weeks, when After about 40 weeks, when the baby is fully developed, the baby is fully developed, the following happens:the following happens:

1.1. The sac of protective fluid The sac of protective fluid breaks openbreaks open

2.2. The muscles of the uterus / The muscles of the uterus / womb contract very strongly womb contract very strongly to push the baby outto push the baby out

3.3. After the baby is born, the After the baby is born, the placenta is also pushed out placenta is also pushed out of the wombof the womb

4.4. The umbilical cord between The umbilical cord between baby and placenta is cutbaby and placenta is cut

ContraceptionContraception

Main methods of preventing conception:Main methods of preventing conception:

1.1. Chemical - prevention of gamete Chemical - prevention of gamete formation e.g. the Pillformation e.g. the Pill

2.2. Physical barrier – preventing the Physical barrier – preventing the gametes from meeting e.g. condomgametes from meeting e.g. condom

3.3. Timing – avoiding sexual intercourse Timing – avoiding sexual intercourse during the fertile period of the during the fertile period of the menstrual cyclemenstrual cycle