Lec.5 FERTILIZATION

Question 1

-is the process by which the
spermatozoon and the egg unite.

-union of the male and female pronuclei.

Answer 1

Fertilization

Question 2

duration of copulation in
ruminants -
horses -
pigs -
dogs -

Answer 2

ruminants - less than a minute

horses - few minutes longer

pigs - several minutes

dogs - 5-30 minutes

Question 3

act of mating.

Answer 3

copulation

Question 4

What animals have the semen deposited in the vagina?

Answer 4

cows, sheep, rabbit, dog, cat, primates

Question 5

what animals have the semen ejaculated directly into the cervix and/or the uterus.

Answer 5

pigs, horses, camelids

Question 6

what is the volume of sperm in ruminants (concentrated with spermatozoa)

Answer 6

3-4 mL

Question 7

what is the volume of sperm in boar (low concentration of spermatozoa)

Answer 7

200-400 mL

Question 8

what is the animal that ejaculates in a series of ‘jets’, of which the first usually contains the fraction rich in spermatozoa.

Answer 8

Stallion

Question 9

what is the volume of sperm in dogs

Answer 9

1-85 mL

Question 10

what is the volume of sperm in cats

Answer 10

0.2-0.3 mL

Question 11

Retrograde loss of spermatozoa from the
female genital tract depends on:

Answer 11

the volume

the physical nature of the ejaculate

the site of its deposition within the female genital tract

Question 12

what animal releases thick coagulum in their last ejaculation to act as ‘plugs’, preventing backflow of semen.

Answer 12

pigs

Question 13

Spermatozoa are not able to fertilize the oocyte immediately after arrival in the female genital tract, they need to ____ themselves first.

Biochemical changes will occur in the sperm, and this usually occurs in the uterus / cervix.

Answer 13

capacitate

Question 14

this surrounds the oocyte and is critically involved in fertilization: such as

the adhesion and binding of capacitated spermatozoa

the induction of the acrosome reaction and penetration

the fertilization-induced modifications that prevent polyspermy

Answer 14

zona pellucida

Question 15

The zona pellucida has species- specific receptors for spermatozoa.

Sperm that comes in contact with ZP will undergo ____.

Answer 15

firm binding

Question 16

Once bound, the sperm will release hydrolytic enzymes (acrosin and hyaluronidase) from its acrosome.

This will allow the sperm to penetrate the ZP in combination with the propulsive movement of its tail.

Answer 16

Acrosome reaction

Question 17

*Fusion of the gametocytes

After penetration of the ZP, sperm adhere to and fuse with the plasma membrane of the oocyte.

The fertilizing spermatozoon will be engulfed by the oocyte.

This process is referred to as?

Answer 17

syngamy / fertilization

Question 18

Once a sperm has entered, the cortical granules from the oocyte will stimulate the modification of the oocyte membrane and the ZP.

This will induce ____, which won’t allow entry of any other sperm.

Answer 18

zona block

Question 19

Once Oocyte activation happens, meiosis will resume in the oocyte, creating a ____.
The tail of the spermatozoon detaches and degenerates.

Answer 19

second polar body and a zygote