Fertilisation I

Question 1

What occurs in fertilistaion?

Answer 1

The union of mae and female gametes

Question 2

Result of fertilisation?

Answer 2

Production of an embryo

Question 3

Stage 1 of fertilisation?

Answer 3

Sperm capacitation

Question 4

What follows sperm capacitation in fertilisation?

Answer 4

Sperm acrosome reaction and binding to the oocyte zona pellucida

Question 5

What follows acrosome reaction and binding to the oocyte ZP?

Answer 5

Sperm-egg plasma membrane binding and fusion

Question 6

What follows sperm-egg plasma membrane binding and fusion?

Answer 6

Oocyte activation

Question 7

What is oocyte activation?

Answer 7

Activation of development

Question 8

What does oocyte activation include?

Answer 8

Completion of maternal (oocyte) meiosis, and embryonic genome activation in mouse and human

Question 9

What does oocyte activation conclude with?

Answer 9

Congregation of paternal and maternal chromosomes in the new one cell embryo

Question 10

Where does sperm capacitation occur?

Answer 10

Female reproductive tract

Question 11

What is sperm capacitation necessary for?

Answer 11

Hyperactivated motility, acrosome reaction and ZP/plasma membrane binding

Question 12

What partly mediates sperm capacitation?

Answer 12

Female reproductive tract

Question 13

What happens to the sperm surface in sperm capacitation?

Answer 13

Modification or removal of sperm surface components
Distribution (domain rearrangement)
COnformational changes

Question 14

What happens to the surface charge of the sperm in sperm capacitation?

Answer 14

There is a decrease in surface net -ve charge

Question 15

What happens to the membrane permeability in sperm capacitation?

Answer 15

There are changes in the membrane permeability to ions (e.g. Ca2+)

Question 16

Human sperm head layers (outside in)?

Answer 16

Plasma membrane–>Outer acrosomal membrane–> inner acrosomal membrane–> matrix–>Nuclear envelope

Question 17

What is the matrix in the sperm head called?

Answer 17

Perinuclear theca

Question 18

What are the two main classes of sperm head morphology?

Answer 18

Crescent and spatulate

Question 19

Examples of animals with a crescent sperm head morphology?

Answer 19

Mouse, rat, goat

Question 20

Examples of animals with a spatulate sperm head morphology?

Answer 20

Pig, human, cattle

Question 21

What is the acrosome reaction required for?

Answer 21

Sperm oocyte plasma membrane binding and fusion

Question 22

What is the acrosome reaction dependant on?

Answer 22

Ca2+

Question 23

What type of event is the acrosome reaction?

Answer 23

Ca2+-dependent exocytosis event

Question 24

What happens to the sperm membranes as a result of the acrosome reaction?

Answer 24

The sperm membranes fuse

Question 25

What was the old idea of how the acrosome reaction was triggered (NOT CORRECT)?

Answer 25

AR thought to be triggered by sperm binding to the zona pellucida (ZP)

Question 26

What is the cumulus oophorous?

Answer 26

A cloud of cumulus cells surrounding the oocyte

Question 27

What must travel through the cumulus oophorus?

Answer 27

Fertilising sperm

Question 28

What does the acrosome reaction occur before?

Answer 28

ZP contact

Question 29

When is the AR induced?

Answer 29

During the sperm's travel through the cumulus oophorus

Question 30

What is acrosin?

Answer 30

Acrosome-specific serine protease