Fertilisation

Question 1

Male prep for fertilisation

3

Answer 1

• penis stimulates becoming sufficiently intense
• rhythmic contractions of epididymis, vas deferens and 3 glands causing ejaculation
• rapid heart beat, increasing bp and breathing rate and an orgasm (pleasant sensation)

Question 2

Ejaculation

Answer 2

when semen propels into urethra and out of the body

Question 3

Female prep for fertilisation

3

Answer 3

• erectile tissue of vulva fills with blood when sexually stimulated
• secretion of mucous lubricate epithelial lining of vagina
• when sexual arousal reaches sufficient intesnity, orgasm or climax occurs

Question 4

Differences between female and male prep for fertilisation

2

Answer 4

female doesn’t need to reach climax for fertilisation and no ejaculation occurs

Question 5

Insemination

Answer 5

process where sperm is released (deposited) into vagina

Question 6

Pathway of sperm in fertilisation

Answer 6

vagina -> cervix -> uterus -> uterine tubes

Question 7

Why don’t all sperms reach the uterine tubes

Answer 7

bc of their high mortality rate

Question 8

Fertilisation def

2

Answer 8

the fusion of a sperm and egg
occurs in the uterine tube when the egg is a third down the tube

Question 9

Corona radiata

2

Answer 9

layer of follicular cells surrounding the mature egg, held together by an acid
many sperm work together to break down the corona radiata, allowing one to accomplish fertilisation

Question 10

What happens once the sperm has entered the egg

6

Answer 10

• sperm stimulates formation of fertilisation membrane, preventing entrance of other sperm
• acrosomal reaction releases enzymes to break down zona pellucida
• egg completes Meisosis II
• sperm tail is absorbed and head begins to move through the cytoplasm of egg in the form of a male pronucleus
• egg nucleus forms into a female pronucleus
• pronuclei fuse together forming a single nucleus with a 2n chromosomes

Question 11

Zona pellucida

Answer 11

a glycoprotein matrix that is the inner layer surrounding the plasma membrane of the secondary oocyte