Reproductive System: Fertilisation

Question 1

Where is semen stored in the cervix and what is it nourished by?

Answer 1

cervical crypts

cervical mucus

Question 2

How long does sperm last and how long does an oocyte last?

Answer 2

~48 hours

~14 hours

Question 3

How are the majority of sperm lost? (4)

Answer 3

destroyed by vaginal acid
fail to penetrate cervical mucus
destroyed by defense cells
enter wrong oviduct

Question 4

How do sperm move?

Answer 4

tail lashing

Question 5

Where does capacitation occur, how long does it take and what two things occur?

Answer 5

isthmus of oviduct
~10 hours
sperm become hyperactive; tails beat more vigorously
sperm prepare for acrosome reaction

Question 6

What two things does the sperm go through during acrosome reaction?

Answer 6

protein coat (zona pellucida)
follicular cells

Question 7

How is polyspermy blocked? (2)

Answer 7

depolarization (Na+ influx)

cortical granule reaction (Ca2+ influx) hardens zona pellucida

Question 8

What is cleavage?

Answer 8

division of a fertilised egg

Question 9

What is a oocyte called with lots of divisions inside?

Answer 9

morula

Question 10

What does a oocyte become when the zona pellucida disappears?

Answer 10

blastocyst

Question 11

What do embryoblast cells become and where are they located within blastocyst?

Answer 11

become embryo

located in the middle and down the bottom of oocyte

Question 12

What do trophoblast cells become and where are they located within the blastocyst?

Answer 12

become foetal part of placenta

located around the edges

Question 13

What do cytotrophoblast cells become and where are they located?

Answer 13

become part of the foetal placenta

located underneath the bottom trophoblasts

Question 14

What do the syncitiotrophoblast cells do and where are they located?

Answer 14

secrete: digestive enzymes and hCG hormone

ooze from underneath the cytotrophoblast cells