Reproductive Flashcards
Gonad formation
Formed from the gonadal ridges. Are in the upper lumbar region (back)
Moving testes
In humans the testes migrate through the abdomen and into the scrotum during development. Probably controlled by androgens.
Gubernaculum
A ligament attaches the testes to the posterior abdominal wall that does not elongate with body growth. Drags the testes down.
The female gubernaculum
Gives rise to the round ligament and aids in mullerian development
Cryptorchidism
Failure of the testes to descend. Some species have it naturally. Results in arrested spermatogenesis. Normal endocrine function
Monotremes
Means one hole. Monotremes are permanently cryptorchid. Some species have testes that move between the scrotum and the abdominal cavity.
Temp of testes
The testes in the scrotum have a temperature 4-7 degrees lower than core body temperature. The effects of cryptorchidism can be mimicked by warming the testes
What separates the chambers of the testes
Perineal raphe
Cremaster muscle
Lies under the skin of the scrotum and control the location of the scrotum relative to the body. Contracts in response to cold to draw the testes closer the body.
Testicular structure- fibrous sheath and lobule name
Each testicle is covered by a fibrous sheath called the tunica albuginea. Each testicle is divided into lobules containing seminiferous tubules.
The cycle of the seminiferous epithelium
Time taken for a sperm to be produced from a germ cell is constant. In any one section, all parts of the production of sperm are synchronised. A cycle is every 16 days
Spermatogenic wave
Responsible for continuous supply, each segment is a stage ahead of the preceding segment
Epididymis
A muscular tube with an epithelial pseudostratified lining. Site of sperm maturation. Sperm spends 13 days
Head (caput)
Receives sperm from rete testis. Contains stereocilia for absorption of fluid. Sperm cannot fertilise and can not move.
Body (corpus)
Convolutions decrease and fluid content decreases
Tail (caudal) of epididymis
Stereocilia reduced
Muscularity increased - moving to three layers. Sperm moves by peristaltic action. Sperm now more concentrated. Epididymis are capable of fertilisation and move
Vas Deferens
Sperm storage. 3 muscular layers. Inner longitudinal layer, middle circular layer, outer longitudinal layer.
Just prior to the prostate gland the lumen becomes enlarged and folded with many crypts. Additional sperm storage called ampulla
Absence of Vas Deferens
Congenital absence of the Vas (CAVD). Common in men with cystic fibrosis. Usually bilateral both vas are missing and though to be due to genetic mutations
What do the ligaments suspending the uterus and ovaries do?
Position the organs because they don’t want movement and correctly align them as the fallopian tubes are connected to the uterus but not the ovaries
What does the ovarian ligament do?
Connects the ovaries to the uterus
What does the ovarian cycle do?
Allow production of oocyte that is ready to be fertilised. Oocytes are produced during gestation
What does the broad ligament do?
Stops lateral movement of the uterus
What does the suspensory ligament do?
Connects the ovaries to the pelvic wall and contains the ovarian arteries/veins
Primordial follicle
Resting - flattened granulosa cells
Primary follicle
Activated - single layer of cuboidal granulosa cells
Secondary follicle
Multilayered granulosa cells
Tertiary follicle
Antrum formed
How long does it take from the time activation to when a follicle forms an antrum and is capable of ovulation
85 days
Which position does the uterus face?
Anteverted, ie the top of the uterus faces forwards. Fetus has to turn 90º to be born via the vagina
Uterus properties
7.5cm long and pear shaped
Non-pregnant uterus has a luminal volume of 10mls
Pregnant uterus contain 5L of baby, amniotic fluid and placenta.