Fertilization

Question 1

Define Fertilization

Answer 1

when male and female gamete unite to form zygote

Question 2

What makes up the cumulus oophorus cells?

Answer 2

granulosa cells around ovulated oocyte

Question 3

Which glycoproteins of the zona pellucida are important in fertilization?

Answer 3

ZP1, ZP2 and ZP3 (most important)

Question 4

Zona pellucida is porous because

Answer 4

to allow granulosa cells to communicat with oocyte

Question 5

Space between plasma membrane of oocyte and ZP is

Answer 5

Periviteline space

Question 6

2 things that need to occur for sperm in oviduct

Answer 6

1. capacitation (Isthmus)

2. hyperactive motility

Question 7

4 results of capacitation on the sperm

Answer 7

1. Loss of membrane cholesterol
2. Increase in pH
3. Changes in intracellular Ca
4. Hyperactivation: change in tail function

Question 8

Result of hyperactivation on cell

Answer 8

increase in cAMP

Question 9

Where does acrosome reaction occur?

Answer 9

Ampulla

Question 10

ZP3 of zona pellucida binds to what?

Answer 10

zona binding region

Question 11

Define the acrosomal reaction

Answer 11

fusion of sperm plasma membrane to outer acrosomal membrane

Question 12

What is released during the acrosome reaction that goes through ZP?

Answer 12

hydrolytic enzymes: hyluronidase and acrosin

Question 13

What do is zona block and what granules are involved?

Answer 13

cortical granule exocytize from oocyte and cause hardening of zona pellucida to prevent polyspermy

Question 14

What is membrane block?

Answer 14

oocyte plasma membrane/ vitteline changed to block polyspermy

Question 15

What binding activates acrosomal reaction region?

Answer 15

ZBR to ZP3

Question 16

What membranes remain after acrosome reaction?

Answer 16

inner acrosome region and nuclear membrane

Question 17

What region is exposed after acrosome reaction?

Answer 17

Equatorial region w/ fusion proteins: binds to oocyte membrane

Question 18

After acrosome reaction creates a pore in ZP what gets sperm to actually go through this channel?

Answer 18

ZP2 pulls on sperm and hyperactivation of tail

Question 19

Inner acrosomal membrane fuses with what?

Answer 19

oocyte plasma membrane/ vitelline membrane

Question 20

What is the actual process to continue metaphase 2 arrest?

Answer 20

Fertilization: causes influx of calcium which decreases maturation promoting factor which allows oocyte to enter anaphase II

Question 21

What proncleus is larger?

Answer 21

Male pronucleus

Question 22

What is syngamy?

Answer 22

fusion of pronuclei to make zygote (completion of fertilization)