Flashcards in reproductions Deck (13)
Name the three main classes of sex steroids, the chemical from which they are all produced and how their biosynthesis is related (3 marks).
-estrogens are formed from androgens
-androgens are formed from progestagens
-all sex steroids are formed from cholesterol
The major male sex steroid is _____________________.
Dihyrotestosterone is produced in the __________________
Dehydroepiandrosterone (DHEA) is produced in the _______________________.
The third peak in androgens in males occurs ___________________________
(when) and causes _________________________________.
formation of penis, scrotum and testes
The major sex steroid in females is ___________________________.
The major progestin is ________________________.
Describe the role of the following in male development:
part of Y chromosome that stimulates the development of testes from the undifferentiated gonad
hormone produced by testes that inhibits the development of the oviducts and uterus
In both males and females, puberty is caused by __________________
-increased production of GnRH from the hypothalamus - in a pulsatile pattern
List a structural change and a functional change that occur as a primordial follicle
becomes a primary follicle.
-structure=cells that surround the oocyte become several layers thick
-function=begins to produce estrogens
List a structural change and a functional change that occur as a secondary follicle
becomes a tertiary follicle.
structure=development of a fluid-filled antrum
-function=increased pressure in antrum promotes ovulation
Name the two main ovarian cycle stages and the two main uterine cycle stages, list
the main event in each and how they are related in terms of time as well as function
the ovarian cycle includes a follicular stage (first 2 weeks) and a luteal stage (last 2 weeks)
-several follicles mature during the follicular stage and produce estrogen
-after ovulation the remnants of the follicle form the corpus luteum which releases progesterone as well as estrogen (luteal stage)
-the menstrual cycle includes a proliferative stage (first 2 weeks) and a secretory stage (last 2 weeks)
-the proliferative stage involves the growth of glands and thickening of the endometrium
-during the secretory stage, endometrial glands mature and secrete a nutrient rich fluid