Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Rachael Phase 1 > Embryology > Flashcards

Embryology Flashcards

1
Q

How many genes are there in the human genome?

A

23,000 genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a primordial follicle?

A

A primary oocyte together with its surrounding flat epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the diplotene stage?

A

Primary oocyte resting stage during prophase characterised by a lacy network of chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How is the arrested state of primary oocyte a produced?

A

Oocyte maturation inhibitor (OMI)- a small peptide secretes by follicular cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Approximately how many primary oocytes are there at birth?

A

600,000-800,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How many oocytes are present at puberty and why is this?

A

40,000 as most oocytes become atretic during childhood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are female monthly cycles controlled by?

A

The hypothalamus produces GnRH, which acts of cells of the anterior lobe of the pituitary gland which in turn secrete gonadotropins (FSH and LH) which stimulate and control cyclic changes in the ovary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which hormone stimulates growth?

A

FSH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Under normal conditions how many follicles reach full maturity?

A

One and one oocyte is released

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Proliferation of granulosa cells is mediated by…

A

Growth differentiation factor 9 (member of TGFbeta)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is oestrogen produced by theca interna and granulosa cells?

A

Theca interna cells produce androstenedione and testosterone and granulosa cells convert these hormones to oestrone and 17b-oestrodiol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why does the corpus luteum shrink?

A

Luteolysis- degeneration of the lutean cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does the corpus luteum turn into after degeneration?

A

A mass of fibrotic scar tissue- the corpus albicans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Removal of the CL before which month usually leads to abortion?

A

4th month

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where does fertilisation occur?

A

The ampulla of the uterine tube (widest part of tube closest to the ovary)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What percentage of sperm from the cervix enter the vagina?

A

1%

17
Q

Are sperm able to fertilise the oocyte immediately upon arrival at the ampulla?

A

No they must first undergo capacitation and acrosomal reaction.

18
Q

What is capacitation?

A

Removal of glycoproteins coat and seminal plasma proteins from the plasma membrane overlying the acrosomal region of the spermatozoa

19
Q

How long does capacitation take?

A

Approx 7 hours

20
Q

What does capacitation allow spermatozoa to do?

A

Pass through coronal cells and undergo the acrosomal reaction

21
Q

What are the spermatozoa phases of fertilization?

A

1) penetration of the corona radiata
2) penetration of the zone pellucida
3) fusion of the oocyte and sperm cell membranes

22
Q

What is the acrosome reaction induced by?

A

Zone proteins

23
Q

What is the acrosome reaction?

A

Release of enzymes (acrosin and trypsin like substances) to penetrate the zone pellucida

Rachael Phase 1 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions