Sexual Intercourse

Question 1

Intercourse

Answer 1

During intercourse the mans penis fills with blood and becomes hard enough to be placed inside the woman’s vagina.

• a mixture of sperm cells and seminal fluid called semen is released into the vagina.
• the sperm swim up the uterus and into the Fallopian tubes.

Question 2

Fertilisation

Answer 2

If an egg is present in the Fallopian tube,and a couple have sexual intercourse,then one of the sperm cells may fuse with it.

The nuclei of sperm and egg fuse together to form a fertilised egg,called a zygote.

Question 3

Implantation

Answer 3

The embryo embeds itself into the uterus wall.

Pregnancy:The uterus lining does not break down so menstruation stops during pregnancy.The average length of a human pregnancy is 40 weeks

-As the embryo develops in the uterus it is protected inside a bag of fluid called amniotic fluid,this fluid provides a cushion for the embryo.

Question 4

Zygote -embryo-foetus

Answer 4

• egg and sperm fuse to form a single
• zygote
• cell division occurs and growth
• Embryo,which attaches to the lining of uterus (implantation)grows more,and after 8 weeks

Question 5

Umbilical cord

Answer 5

A tube called the umbilical cord joins embryo to the placenta.

Question 6

Placenta

Answer 6

The placenta is rich in blood vessels
It is here at the placenta that flood and oxygen from the mothers blood pass into the baby’s blood
Also wastes wastes such as carbon dioxide pass from the baby’s blood into the mothers

Question 7

Birth

Answer 7

The birth of a baby begins when the uterus muscles start to contract
This is called labor
The bag of amniotic fluid bursts waters break and further contractions push the baby out usually head first,through the vagina.

Question 8

Afterbirth

Answer 8

The umbilical cord is cut and the placenta (afterbirth) come out after

Question 9

Lactation

Answer 9

The mother may choose to breastfeed the infant.
The production of breast milk is called lactation
The first three days of milk is called colostrum-very nutritious, and helps protect the baby from infection

Question 10

Family planning

Answer 10

• to control the number of children you have you need to control the number of times fertilisation takes place.
• natural methods of contraception aim to detect the day ovulation takes place and avoid intercourse during the fertile period .

Question 11

Artificial methods of contraception

Answer 11

An example of this is a condom which prevents sperm entering the vagina
Another example is the contraceptive pill which prevents ovulation.