1B4 Human Reproduction www.juniorscience.ie

The female reproductive system The ovaries produce the female gamete (egg) produce the hormone oestrogen. www.juniorscience.ie

The male reproductive system The testes produces the male gamete (sperm) produces the hormone testosterone. Penis Sperm duct Testes urethra Seminal vesicle

The Human Reproductive system This is usually an awkward section for students because it is very close to home! It is important to present the facts but have a sense of humour when the nervous giggles erupt. With this opening slide I would hope it would let them laugh and relax. As an introduction, a clip (first 3 min only) from the ‘science unleashed’ video on ‘Human Reproduction, could be played. It is hyperlinked to the baby image on slide. Brain storm, using the board, what the students know already about the topic. Then give a run down on what will be covered in this section; male and female reproductive systems menstrual cycle fertilization and pregnancy contraception

Sperm cell =25mm The Testes start to make sperm at Puberty 1/40 th of a millimetre!!!!! The Testes start to make sperm at Puberty Explain that the sperm is the male sex cell or Gamete and contains half the information needed for a new human being. Give a minute for the students to draw this diagram into their copies. Sperm and Seminal Fluid together is called Semen

Growth & Puberty Puberty is the time during which the sex hormones are produced. In boys, the voice deepens and body hair grows In girls ovulation starts and breasts develop. www.juniorscience.ie

The menstrual cycle 28 day cycle in the female link to animation 28 day cycle in the female Controlled by chemicals called hormones An egg is produced, and the womb develops a thick lining of blood vessels to be prepared for pregnancy If the egg is not fertilised, the lining leaves the womb – menstruation – and the cycle begins again www.juniorscience.ie

Stages in the menstrual cycle 28 day cycle Approx. days 1 - 5 Menstruation – loss of uterus lining 5 - 13 Repair of uterus lining 14 Ovulation - Release of egg from ovary 14 - 28 Uterus lining remains built up www.juniorscience.ie

Release of womb lining and blood. Fertile period This is the time in the menstrual cycle that a woman can become pregnant. Ovulation The release of an egg from the ovary. Menstruation Release of womb lining and blood. www.juniorscience.ie

link to ‘how stuff works’ animation Sexual intercourse The natural process of transferring the sperm from the body of a male to the body of a female link to ‘how stuff works’ animation www.juniorscience.ie

Implantation The embedding of the embryo in the womb wall

Fertilisation Occurs when a male gamete (sperm) fuses with the female gamete (egg) to form a zygote Also referred to as conception Sperm + egg = zygote www.juniorscience.ie

Fertilisation Fertilisation usually happens in the oviduct / fallopian tube A fertilised egg – zygote - may then move down into the wall of the uterus / womb www.juniorscience.ie

Pregnancy Changes that occur in a woman's body after fertilisation: The menstrual cycle stops The embryo implants in the womb The placenta develops link to animation www.juniorscience.ie

Pregnancy The zygote develops into a foetus. The baby forms over 40 weeks. It develops inside a protective sac of amniotic fluid. Food and oxygen pass from mother to baby through the placenta and umbilical cord. Carbon dioxide and other wastes pass from baby to mother to be excreted. www.juniorscience.ie

Birth The changes that occur during birth: Link to birth animation The changes that occur during birth: The sac of protective fluid breaks open The muscles of the uterus / womb contract very strongly to push the baby out After the baby is born, the placenta is also pushed out of the womb The umbilical cord between baby and placenta is cut Links to an animation – may be slow to load… www.juniorscience.ie

Contraception Main methods of preventing conception: Chemical - prevention of gamete formation e.g. the Pill Physical barrier – preventing the gametes from meeting e.g. condom Timing – avoiding sexual intercourse during the fertile period of the menstrual cycle www.juniorscience.ie

Find the answers: Why are human babies born so “helpless” compared to some animal babies? Why are human babies’ heads so big in comparison to their bodies? What are conjoined twins and how do they occur? What is foetal alcohol syndrome ? www.juniorscience.ie

1B4 Human Reproduction www.juniorscience.ie

www.juniorscience.ie