Hormonal Control Of Reproduction Flashcards
What are hormones?
Hormones are chemical messengers produced by an endocrine gland and secreted directly into the bloodstream
What stimulates the pituitary gland to release hormones?
A released hormone produced in the hypothalamus
What hormones does the pituitary gland release?
Follicle Stimulating Hormone ( FSH )
Luteinising Hormone ( LH )
Interstitial Cell Stimulating Hormone ( ICSH )
Which hormone is released by the pituitary gland in both sexes?
FSH ( follicle stimulating hormone )
Which hormone is release by the pituitary gland in females?
Luteinising hormone ( LH )
Which hormone is released by the pituitary gland in males?
Interstitial cell stimulating hormone ( ICSH )
What hormone does the hypothalamus release to regulate the pituitary gland?
The hypothalamus releases a releaser hormone.
What is the function of releaser hormones?
Releaser hormones control and regulate the actions of the pituitary gland.
What is a gonad in terms of the reproductive system of both men and women?
Testes for men and Ovaries for women
( organ that produces gametes )
What does FSH ( follicle stimulating hormone ) promote in men?
FSH promotes the production of sperm
What does ICSH ( interstitial cell stimulating hormone ) stimulate in men?
ICSH stimulates the production of testosterone
What is the role of testosterone in men?
Testosterone stimulates sperm production and activates the prostate gland and seminal vesicles
What is the production of testosterone controlled by?
Negative feedback by FSH ( follicle stimulating hormone ) and ICSH ( interstitial cell stimulating hormone )
How many days approximately does the menstrual cycle take?
28 days
What is considered day one of the menstrual cycle?
Day one of the cycle is when menstruation occurs.
What does FSH ( follicle stimulating hormone ) stimulate in women?
FSH stimulates the development of a follicle and the production of oestrogen by the follicle in the follicular phase.
What are the 2 stages of the menstrual cycle?
The follicular phase and then the luteal phase.
What does oestrogen secreted by a follicle cause?
Oestrogen stimulates the proliferation ( expansion ) of the endometrium preparing it for implantation and affects the consistency of cervical mucus making it more easily penetrated by sperm
What do peak levels of oestrogen stimulate?
Peak levels of oestrogen stimulate a surge in the secretion of LH ( luteinising hormone )
What does LH ( luteinising hormone ) cause in women?
LH causes ovulation around the 14 day mark of the menstrual cycle, releasing the mature ovum from the follicle in the ovary.
What occurs in the luteal phase?
In the luteal phase the follicle develops into a corpus luteum which secretes progesterone
What does progesterone cause in women?
Progesterone promotes further development and vascularisation of the endometrium, which prepares it for implantation if fertilisation occurs.
What prevents further follicles from developing?
The negative feedback effect of the ovarian hormones on the pituitary gland and the secretion of FSH and LH
What does a lack of LH ( luteinising hormone ) cause?
A lack of LH causes the degeneration of the corpus luteum with a subsequent drop in progesterone levels leading to menstruation to occur again.
What happens in terms of the corpus luteum if fertilisation occurs?
The corpus luteum doesn’t degenerate and progesterone levels remain high, maintaining the development and vascularisation of the endometrium.
What can high levels of oestrogen cause?
The proliferation of the endometrium, the thinning of cervical mucus to allow for sperm penetration and the production of LH.
