Lecture 31 Male Reproductive Sytem Flashcards
What are gonads?
The reproductive organs that produce gametes Testes for males Ovary for females
At what age does sexual maturity usually occur in m’s and f’s
M- 12 to 16 F- 10 to 14
Briefly state the function of the Testes
The Primary sex organ that produces sperm and sex harmones
Briefly state the function of the Epididymis
The sites of maturation, where spermatozoa gain the ability to swim, and some are stored
Briefly state the function of the Vas Deferens
Conduct and store sperm
Briefly state the function of the Urethra
Conducts sperm and urine
Briefly state the function of the Penis
Organ of copopulation
The testes are suspended in the x, in order to y
The testes are suspended in the scrotum in order to regulate the testicular temperature
Where does the testes develop, and when does it descend into the scrotal sac?
It develops inside the abdominal cavity, and descends into the Scrotal sac during the last 2 months of fetal development.
What does an undescendant testes lead to?
Sterility
Testes consists of lonules containing x tubules
Seminiferous tubules -enclosed by Basal Lamina - contains Sertoli cells, that possess FSH receptors; support, nourish and regulate spermatogenic cells. -sperms cells are created here, from spermatogonia to immature spermatozoa
What are interstitial tissue?
Cells that are the located in the spaces between the tubules. Leydig cells- poses LH receptors that stimulate Testosterone production. ؟Myoid cells?- sorround Basal Lamina- smooth muscle cells that allow lumen to contract to move the immobile spermatozoon to the epididymis.
Describe the process of Spermatogenesis
(1)Spermatogonium(2n)- germinal cells divide by mitosis—> (2) primary spermatocyte (2n) divide by mitosis to produce MORE primary spermatocytes OR divide by meiosis I to produce (3) secondary spermatocytes (n) which divide by meiosis II to give (4) early spermatids which differentiate to (5) late spermatids which differentiate to (6) Spermatozoon
When does spermatogenesis start? And how long does it take to complete?
Around the age of 13 years Approx 74 days to complete
How many speeds are produced every day approx?
120 million sperms (60-150 million)/day
What is Spermiogenesis?
Early spermatids till the production of spermatozoa in the seminiferous tubules. Mediated by Sertoli cells that phagocytize the excess cytoplasm to give spermatozoa,
What are the 3 parts of sperm?
Head- contains large nucleus and acrosome (special type fo lysosome used to penetrate egg) Middle piece- contains spiral shaped mitochondria to give sperm energy to move Tail- made out of microtubules as component of flagellum. Allows sperm to swim to egg.
In what way do the sperms become more resistant when they enter the epididymis?
-More resistant to PH (it is more acidic while spermatozoa are optimal at alkaline PH) -more resistant to Temp (it is warmer than testes)
Are most sperms stored in the epididymis or van deferens?
Vas deferens
Testicular cancer is common x
In old age (over 50)
What is the percentage of semen is sperm and glandular secretion?
5% sperm 95% glandular secretions
Descrine the seminal vesicles and it’s function
60% of semen Thick viscous fluid that contains fructose (for energy) Prostaglandins- stimulate smooth muscles to contract along the m and f reproductive systems
Descrine the Prostate gland and it’s function
30% of semen Secretes alkaline that increases the motility of sperm (optimal PH)
What is the 2nd most common cancer for males and what is the condition that leads to it?
Prostate cancer Prostate hypertrophy, which results In the Urethra being squeezed- leading to a difficulty in urination
What is the male organ for sexual intercourse and what is the layer it is covered by called?
Penis Foreskin is the covering, it gets removed during male circumcision
What is the benefit of male circumcision?
It decreases the chwnce of acquiring STD’s, such as AIDS by 25-35%
The penis has x columns of y tissue with extensive z extending through the shaft
3 columns of spongy erectile tissue Extensive blood spacing
The 3 columns of spongy erectile tissue consist of 2 x and 1 y
2 corpora cavernosa 1 corpus sporangiosum
What is impotency?
An inability for the penis to become erect Caused by a # of factors such as poor blood flow, some medications and illnesses
Describe the 2 phases of ejaculation
1.Emission Nerve impulses from the spine trigger -the muscular wall of the epididymis and vas deferens to empty the sperm -the reproductive glands to release secretion 2. Expulsion- Gland secretions (prostaglandins of seminal vesicles) stimulate rhythmic contractions of the muscles at the base of the penis abs within the Urethral Wall to expel semen in spurts During ejaculation, the urinary bladder sphincter closes so no semen can enter it
Ejaculation results in the expulsion of (x-y) ml of semen that contains ≈ z million sperms`
2-5bml of semen that contains ≈ 300 mil sperms`
How long can a sperm survive in the female genital tract?
1-3 days
How many sperm reach the egg and how many penetrate?
100-200 reach the egg Only 1 penetrates the egg
Draw the HPT axis
List the functions of Testesterone
- the main sex harmone in males
- imp for development & function of male reproductive glands and organs
- essential for the maturation of sperm
essential for the development of male 2ndary characteristics
- Oil and sweat glands secretion–> acne and body odor
- enlargement of larynx and vocal chords –> deepening of voice
- triggers baldness ( if specific genes are present)
- muscle strength
- height, length of legs, and broad shoulders
- sex drive and aggressiveness
