Reproduction Physiology Flashcards
What is the name for the earliest recognisable germ cell in females?
Primordial germ cell
Primary oocytes are formed after the 1st mitotic division. True/False?
False
1st MEIOTIC division!
What is a polar body in oogenesis?
Small haploid cell formed during meiotic divisions that is not able to be fertilised
What does the presence of 2 polar bodies imply?
Completion of 2nd meiotic division
Entry of sperm into egg
How long does the ovarian (menstrual) cycle normally last?
28 days
What are the 2 phases of the menstrual cycle?
Follicular phase
Luteal phase
What happens in the follicular phase of the menstrual cycle?
Maturation of ovum/preparation for ovulation
Ovulation signals end of follicular phase
What happens in the luteal phase of the menstrual cycle?
Post-ovulatory phase involving development of corpus luteum
Preparation of reproductive tract for pregnancy if fertilisation occurs
What is a primary follicle?
Layer of granulosa cells surrounding a primary oocyte that is capable of producing an ovum
What is a secondary follicle?
Differentiated follicle due to oocyte growth, resulting in some follicles undergoing ovulation (signalling end of follicular phase)
What happens to follicular cells left behind that are not part of ovulation?
Undergo luteinisation - transform into the corpus luteum
What hormone does the corpus luteum secrete?
Progesterone
Oestrogen is secreted in the follicular phase of menstruation; progesterone is secreted in the luteal phase. What is the importance of these hormones to the reproductive tract?
Prepare uterine lining for implantation
How long does the corpus luteum grow for following ovulation?
8-9 days
If fertilisation does not occur, how long will the corpus luteum survive?
Survives no longer than 14 days
The degeneration of the corpus luteum signals the start of the next follicular phase of menstruation. True/False?
True
Which hormone does the hypothalamus secrete to act on the anterior pituitary in hormonal control of the ovaries?
GnRH
Which two hormones are secreted by the anterior pituitary in the female gonadal axis?
LH
FSH
What does FSH do?
Acts on ovary to stimulate production of follicles, and in turn stimulate oestradiol secretion
What does LH do?
Acts on ovary to stimulate follicle maturation, ovulation and development of corpus luteum
Describe levels of FSH, LH, oestrogen and progesterone during the follicular phase of menstruation
FSH rises (to recruit follicles) Oestrogen rises (as follicles develop) Oestrogen stimulates LH rise LH peak just before ovulation Progesterone rise after ovulation
What is the purpose of oestradiol?
Thickens endometrium
Thins cervical mucus
Oestrogen suppresses FSH production. True/False?
True
What are the 3 main clinical signs of detecting ovulation?
High progesterone at day 21
High LH spike
Increase in temp. by 1 degree
How does the corpus luteum “know” if fertilisation has taken place?
hCG production by the embryo at 12 days - if this doesn’t occur, corpus luteum degenerates
What is the corpus albicans?
Remnant/degenerated corpus luteum