Luteal Phase And Fertilisation

Question 0

How does capacitation help with fertilisation?

Answer 0

It helps the sperm to reach and penetrate the egg

Initiated by uterine or uterine tube fluid

Question 1

What is capacitation in terms of sperm change?

Answer 1

Biochemical removal of the surface glycoproteins which initiates the whiplash movement if the sperm tail (becomes hyperactive)

Question 2

What is secreted by the corpus luteum?

Answer 2

Progesterone and oestrogen

Question 3

Why is the removal of the corpus luteum essential to start a new cycle?

Answer 3

Need fall in CL derived steroids to cause inter cycle rise in FSH

Question 4

What is the zona pellucida?

Answer 4

Non cellular barrier secreted by the egg

Sperm binds to it to initiate across me reaction

Question 5

What is the acrosome reaction?

Answer 5

Sperm entry towards the egg
Egg is taken in by phagocytosis
Tail and mitochondria left behind

Question 6

What happens in second meiotic division?

Answer 6

Secondary oocyte releases second polar body on entry of sperm into the uterus

Question 7

What happens in fertilisation?

Answer 7

Nucleus from sperm changes into pronucleus
Chromosomes condense
Male and female pronuclei slowly come together
Membranes break down
Alignment of chromosomes on spindle –> mitosis, 2 cells