Human sexual reproduction.

Question 1

Structure and function of the male reproductive system.

Answer 1

Testes: produce sperm (seminiferous tubules) and testosterone (leydig cells), surrounded in scrotum sac oiutside body=reduce temp
Vas deferens: tube connecting epididymis and urethra
Penis: site of sexual intercourse, site of urination
Epididymis: stores sperm to become mature and more mobile
Seminiferous tubules: sperm are made here
Urethra: carries semen or urine out of the body
Prostate gland: releases more fluid to nourish sperm, alkaline pH, neutralise acidic vagina
Seminal vesicle: produces secretions to aid sperm mobility, sperm+secretions–> semen.

Question 2

Function of male reproductive system.

Answer 2

To make sperm/spermatogenesis
Site of sexual reproduction
Testosterone production.

Question 3

Sperm structure and function.

Answer 3

Flagella: movement towards egg
Mitochondria (midpiece): produce ATP for flagella
In head: haploid nucleus, acrosome (contains hydrolytic enzymes which digest the outer layer of the egg).

Question 4

Process of spermatogenesis.

Answer 4

Germinal cells (2n)
Mitosis to 2 spermatagonia (2n)
Mitosis & growth to 4 primary spermatocytes (2n) : some regenerate to germinal epithelial
Meiosis 1 to 2 secondary spermatocytes (n)
Meiosis 2 to 4 spermatids (n)
Differentiation to sperm.

Question 5

Hormone definition.

Answer 5

Secreted by endocrine glands
Travel in blood
Bind to a complementary receptor on a cell.

Question 6

Cross section of seminiferous tubules.

Answer 6

Outside–>inside
Leydig cells: produce testosterone
Germinal epithelial cells & spermatagonia
Primary and secondary spermatocytes
Spermatids
Lumen: immature sperm enter here and drain into the epididymus
Sertoli cells: nourish developing cells, protects sperm cells from the immune system.

Question 7

Structure and function of the female reproductive system.

Answer 7

Ovary: produces eggs/oogenesis, produces progesterone and oestrogen
Oviduct/fallopian tube: connects ovary and uterus, egg travels due to movement on cilia on ciliated epithelium, site of fertilisation
Uterus/womb: endometrium=uterus lining, site of implantation of fertilised egg, shed monthly if no implantation, myometrium= smooth muscle, contracts during labour and menstruation
Cervix: ring of muscle, open during labour, if closed sperm and period blood can still get through
Vagina: acidic pH, muscular tube, site of sexual intercourse and labour.