Fertilzation

Question 1

What is fertilization

Answer 1

Fertilization is the process by which male and female gametes fuse in the ampullary region of the uterine tube

Question 2

What is the widest part of the uterine tube

Answer 2

The ampullary region

Question 3

Movement of sperms from the cervix to the uterine tube occurs by

Answer 3

Muscular contractions of the uterus sha uterine tube and very little but their own propulsion

Question 4

What happens when the sperm reach the isthmus

Answer 4

They become less motile and cease their migration

Question 5

What happens to sperm at ovulation and why?

Answer 5

They become more motile perhaps because of chemoattractants produced by cumulus cells surrounding the egg
And swim to the ampulla where fertilization usually occurs

Question 6

What is capacitation

Answer 6

It is the removal of the glycoprotein coat and seminal plasma proteins from the plasma membrane that overlies the acrosomal region

Question 7

Capicitation lasts approximately how long

Answer 7

7 hours

Question 8

The acrosomal reaction which occurs after binding to the zona pellucida is induced by

Answer 8

Zona proteins

Question 9

The acrosome reaction culminates in what

Answer 9

The release of enzymes needed to penetrate the zona pellucida including acrosin and trypsin like substances

Question 10

The barriers of the oocyte are

Answer 10

First barrier- cells of corona radiata
Second barrier- zona pellucida made up of glycoproteins ZP1, ZP2, ZP3
Third Barrier- viteline membrane

Question 11

Stages of Fertilization

Answer 11

Penetration of corona radiata
Penetration of zona pellucida
Fusion of sperm and oocyte cell membranes
Completion of meiosis II of oocyte and formation of female pro nucleus
Formation of male pro nucleus
Formation of zygote

Question 12

The sperm penetrates freely through the corona radiata and reaches the zona pellucida by

Answer 12

Movement of its tail

Question 13

What does hyaludonirase digest

Answer 13

Hyaluronic acid which is an important constituent of the connective tissue

Question 14

What is the purpose of zona reaction

Answer 14

To prevent other sperms from coming in to the zona pellucida

Question 15

The maternal chromosomes of mature oocyte condense and arrange themselves in a vesicular manner to form

Answer 15

The female pronucleus

Question 16

The nucleus of the sperm swells to become the

Answer 16

Male pronucleus

Question 17

When does the tail of the sperm degenerate

Answer 17

After the male pronucleus is formed

Question 18

The oocyte containing two haploid nuclei is called

Answer 18

Ootid