4: Control of Reproduction Flashcards
(88 cards)
Where are the main reproduction hormones released from?
Anterior pituitary
What are the two groups of reproduction hormones?
- Glycoprotein hormones
- Polypeptide hormones
What are the glycoprotein reproduction hormones? (3 things)
- FSH
- LH
- TSH (thyroid stimulating hormone)
Where are FSH and LH produced?
Gonadotrophs in anterior pituitary
What hormones are termed “gonadotropins”
FSH & LH
Where is TSH (thyroid stimulating hormone) released from?
Thyrotrophs in anterior pituitary
What controls FSH and LH release?
Gonadotropin Releasing Hormone (GnRH)
Where is Gonadotropin Releasing Hormone (GnRH) secreted from?
Hypothalamus
What is the purpose of Gonadotropin Releasing Hormone (GnRH)?
Controls secretion of FSH and LH
What are the fuctions of FSH and LH? (2 things)
- Control gamete production
- Stimulate gonadal steroid secretion (testosterone / oestrogen / progesterone)
Where do FSH and LH act?
Gonads
What are the polypeptide reproduction hormones? (3 things)
- Growth Hormone
- ACTH
- Prolactin
Where is Growth Hormone released from?
Somatotrophs in anterior pituitary
Where is ACTH released from?
Corticotrophs in anterior pituitary
Where is prolactin released from?
Lactotrophs in anterior pituitary
What is testosterones effect on GnRH secretion?
Inhibits GnRH secretion
What is oestrogens effect on GnRH secretion?
Inhibits GnRH secretion
What is progesterones effect on GnRH secretion? (2 things)
- ncreasing oestrogens inhibitory effect on GnRH secretion
- Reduces the frequency of pulses
What does a moderate vs high oestrogen concentration do to GnRH secretion?
Moderate oestrogen: causes low amount of GnRH secretion per pulse
High oestrogen: promotes GnRH secretion (surge)
What inhibits the GnRH surge caused by high oestrogen concentration?
Progesterone
What is inhibin?
Hormone that reduces the amount of FSH released in response to GnRH
Where is inhibin released from?
Granulosa cells in ovaries
What are the 3 stages of the Reproductive cycle?
- Preparation
- Ovulation
- Waiting
How long is the Preparation phase of the Reproductive cycle?
12 days