H UMAN R EPRODUCTION

S EXUAL REPRODUCTION Specialised cells called gametes fuse to produce a gamete Gametes are formed during the process of meiosis

M EIOSIS

T HE STRUCTURE AND FUNCTION OF THE MALE AND FEMALE REPRODUCTIVE SYSTEMS.

T HE F EMALE R EPRODUCTIVE S YSTEM Oviduct or Fallopian tube Uterus Vagina Cervix Ovary

F UNCTIONS OF THE F EMALE R EPRODUCTIVE S YSTEM 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.

W ALLS OF THE O VIDUCT Cilia

F UNCTIONS OF THE F EMALE R EPRODUCTIVE S YSTEM 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.

F UNCTIONS OF THE F EMALE R EPRODUCTIVE S YSTEM 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.

S TRUCTURE 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).

T HE M ALE R EPRODUCTIVE S YSTEM

F UNCTIONS OF THE M ALE R EPRODUCTIVE S YSTEM 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.

F UNCTIONS OF THE M ALE R EPRODUCTIVE S YSTEM 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

F UNCTIONS OF THE M ALE R EPRODUCTIVE S YSTEM 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.

F UNCTIONS OF THE M ALE R EPRODUCTIVE S YSTEM 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.

F UNCTIONS OF THE M ALE R EPRODUCTIVE S YSTEM 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).

S TRUCTURE 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.