HUMAN REPRODUCTION

SEXUAL REPRODUCTION

Specialised cells called gametes fuse to produce a gamete

Gametes are formed during the process of meiosis

MEIOSIS

THE STRUCTURE AND FUNCTION OF THE MALE AND FEMALE

REPRODUCTIVE SYSTEMS.

THE FEMALE REPRODUCTIVE SYSTEM

Oviduct or

Fallopian tube

Uterus

Vagina

Cervix

Ovary Ovary

FUNCTIONS OF THE FEMALE REPRODUCTIVE SYSTEM

Ovaries Small walnut sized

organs where the ova or eggs (the female gametes) are made.

Oviducts Tubes that connect the

ovaries to the uterus. Their walls have cilia on them which beat rhythmically to move the egg down the tube.

WALLS OF THE OVIDUCT

Cilia

FUNCTIONS OF THE FEMALE REPRODUCTIVE SYSTEM

Uterus (or womb) This organ has thick walls made of muscle. It is

where a baby grows. Cervix

At the bottom (neck) of the uterus there is a tight circle of muscle called the cervix. This holds the baby in place during pregnancy.

FUNCTIONS OF THE FEMALE REPRODUCTIVE SYSTEM

Vagina A muscular tube connecting the cervix with the

outside of the woman’s body. It is where the penis is inserted during sexual intercourse and where a baby emerges during birth.

STRUCTURE AND FUNCTION OF THE OVUM

The ovum (pl. ova) is the female gamete. It’s functions are:

To provide half the information required to make a new life.

To allow one sperm to enter the outer wall during fertilisation.

To provide nutrients for the developing zygote (fertilised egg).

THE MALE REPRODUCTIVE SYSTEM

FUNCTIONS OF THE MALE REPRODUCTIVE SYSTEM

Testis (pl = testes) The testes contain thousands of narrow tubes

called tubules where sperm (the male gamete) are made.

Scrotum Sperm need to be made at a cooler temperature

than body temperature. To achieve this they hang outside the male’s body in a sack of skin called the scrotum.

FUNCTIONS OF THE MALE REPRODUCTIVE SYSTEM

Epididymis Contains lots of tubules

where mature sperm are stored ready for ejaculation.

Vas Deferens The tube which carries

the sperm away from the testes

FUNCTIONS OF THE MALE REPRODUCTIVE SYSTEM

Urethra Just below the bladder, the vas deferens joins up

with the urethra. This tube continues out through the penis and can carry either urine or semen (but never at the same time).

Prostate gland The prostate gland sits where the vas deferens

and urethra meet up. It makes a nutritious fluid for the sperm to swim in. Sperm + fluid = semen.

FUNCTIONS OF THE MALE REPRODUCTIVE SYSTEM

Seminal Vesicles These glands also secrete (give out) fluid to

make the semen. Penis

This contains the urethra and erectile tissue. When a man is sexually excited, blood flows into the spaces in the erectile tissue and the penis becomes erect.

FUNCTIONS OF THE MALE REPRODUCTIVE SYSTEM

Foreskin This is a layer of skin that covers the end of the

penis. It can be removed for religious reasons or if it is too tight (circumcision).

STRUCTURE AND FUNCTION OF SPERM

Sperm is the male gamete. It’s functions are:

To provide half the information required to make a new life.

To swim to the ovum. To penetrate the outer wall of the ovum.