Reproductive physiology Flashcards
What decides your gender normally
Biological sex
What r essential precursors 2 pregnancy
production of gametes, and the process of fertilisation, are essential precursors to human pregnancy
What r the major components of the male reproductive system
The major components are testis, epididymis, vas deferens and ejaculatory duct of each side, and the urethra
and penis in the midline
What glands are associated with the system
3 types of accessory glands are associated with the system: A single prostate, a pair of seminal vesicles, a pair
of bulbourethral gland (Cowper’s gland)
What do the testis contain
Seminferous tubules, Leydig & Sertoli cells
What do the seminferous tubules do
produce sperm
What do the leydig cells do
Produce testosterone & some other androgens
What is another name for Leydig cells
Interstitial cells
What does the epididymis do
Sperm are released from the
testis and stored here prior to
ejaculation
What happens at Ejaculation
At ejaculation sperm passes through the
two Vas Deferens (which are contractile),
and are mixed with fluid from the seminal
vesicles
The fluid then leaves the ejaculatory duct,
and passes into the urethra where it
mixes with secretions from the prostate
gland
Describe the hormonal regulation of the male reproductive system
FSH and LF are secreted from the anterior pituitary, stimulated by GnRH from the hypothalamus
Leydig cells respond the LH and secrete testosterone (inhibitory effect on the axis) and other androgens
Sertoli cells are the “Nurse” cells of the testicles and is part of a seminiferous tubule
Activated by FSH and secrete inhibin for negative feedback
What is the function of sertoli cells
Main function is to nourish the developing sperm cell through the stages of spermatogenesis
How many sperm are produced a day
The overall production of sperm is estimated to up to 200 million sperm per day
What is the name of the process and first and final cells that form mature sperm
Spermatogonium (an undifferentiated male germ cell) undergoes spermatogenesis to form mature
spermatozoa
Where are mature spermatozoa found
in the seminiferous tubules of the testis
Describe the names of the cells at each stage of spermatogenesis
Mitotic division of the spermatogonia 1° spermatocytes 1
st mitotic division 2° spermatocytes
(haploid) Spermatids Spermatozoa
What has parallel functions to the testes
AND
What do these organs do
The ovary has parallel functions to the testes, in that they produces the gametes (oocytes) and the steroids
needed for female reproductive function (progesterone and estrogens).
What is the function of the fallopian tube/oviduct
The Fallopian tube (oviduct) through which the oocyte reaches the uterus. It provides an appropriate
environment to sustain either an oocyte or a conceptus
(fertilised oocyte).
What is the function of the uterus
The uterus is where the conceptus normally implants and is
supported throughout pregnancy
Where are thecal AND granulosa cells found
Within developing follicles
What is the function of thecal cells
The thecal cells of the developing follicles are
responsible for production of oestrogen precursor called
androstenedione. They have LH receptors.
What do inner granulosa cells contain that allows them to perform their function
The inner granulosa cells contain aromatase to produce
progesterone and oestrone which turns into oestradiol. They have FSH
receptors
What happens in initial recruitment
Recruitment
Initial recruitment is gonadotrophin independent and involves the
differentiation of primordial follicles into 1° and preantral follicles, the
majority of which undergo atresia(whither away) prior to puberty
What occurs after puberty and is independent of gonadotrophin
Cyclic recruitment occurs after puberty and is gonadotrophin dependent
Describe what cyclic recruitment involves
Cyclic recruitment involves the growth and development of antral follicles through to mature preovulatory follicle selection and ovulation or atresia
How long does cyclic recruitment occur
This process continues throughout a female’s reproductive lifespan until the
primordial follicle pool is depleted
When do secondary oocytes develop
What does it produce
These inactive ovaries persist until puberty when meiosis resumes as 2° follicles develop
o 2° oocyte are formed and are haploid + 1st polar body
How long does the menstrual cycle last
The cycle lasts 21-35 days in adult females, usually 28 days
How long can the menstrual cycle last in extreme cases
younger teenagers may be up to 45 days
What occurs on day 1 & starts the cycle
Menstruation occurs on Day 1 shed blood (20-80ml) and endometrial lining, remaining is a thin basal
endometrium
What does the menstrual cycle consist of
Consists of 2 related cycles: Overian & Endometrial cycle
Describe the phases and lengths of the Ovarian cycle
Ovarian Cycle
Follicular Phase (first 14 days)
Ovulation (mid-cycle) (Day 14) Basal body temperature ↑ 0.5°C
Luteal Phase (next 14 days)
Describe the phases and lengths of the Ovarian cycle
Ovarian Cycle
Follicular Phase (first 14 days)
Ovulation (mid-cycle) (Day 14) Basal body temperature ↑ 0.5°C
Luteal Phase (next 14 days)
What occurs in the follicular phase
Repair and Proliferative Phase
What stimulates the growth of the follicle in the follicular phase
Growth of ovarian follicle stimulated by FSH and LH
What do these follicles produce
These follicles (Thecal and granulosa cells) start growing stimulate and they produce 17BETA-oestradiol
What does 17 beta oestradiol do
17BETA-oestradiol stimulates the proliferation of endometrial cells
Increasing their thickness up to 2-3 fold
o The number and length of glands & length of arteries ↑
What happens at the end of the follicular phase
• At late-follicular phase
-Oestrogen negative feedback to HPG axis switches transiently to positive feedback
causes LH and FSH surge
• LH stimulates ovulation
What happens at the end of the follicular phase
• At late-follicular phase
-Oestrogen negative feedback to HPG axis switches transiently to positive feedback
causes LH and FSH surge
• LH stimulates ovulation
