A&P II Ch. 27 The Male Reproductive System
What is included in the spermatic cord?
-Ductus deferens -Deferential artery -Pampiniform plexus (vein: CO2 rich blood back to heart) -Testicular artery (to testis) -Genitofermoral nerve (sensory and motor)
What is the structure of the sperm?
-Head: contains nucleus. Acrosomal cap contains the enzymes that penetrate the egg during fertilization -Middle piece: contains mitochondria -Tail: flagellum for movement
What are the two functions of the Testis?
-Produce immature sperms -Secrete hormone called androgen, which is testosterone
Sex cells in seminiferous tubules, in order
-Spermatogonium: stem cells, outer 1st layer -Primary spermatocyte: 2nd layer, all cells originate from stem cells -2nd spermatocyte: 3rd, 4th, 5th layer, all but the middle section -Spermatid: immature sperm, middle layer
What are the functions of testosterone?
-Stimulates bone and muscle growth -Establish and maintain male 2nd sex characteristics -Effects on CNS -Maintain accessory glands and organs
What does ejected semen contain?
-sperm (20-100 millions/mL) -seminal fluid which has enzymes -protease -- dissolves mucus secretion in the vagina -semialplasmin -- antibody -prostatic enyme -- convert fibrinogen to fibrin -fibrinolysin -- liquifies the clotted semen that helps neutralize any urinary acids
Function of the Ductus Deferens (Vas Deferens)
1) Transport sperm. 2) Store sperm
What are the functions of Nurse cells (sustentacular cells)
1. Maintain the blood-testis barrier to prevent immune cells from attacking the sperm and nourish the newly formed sperm cells 2. Support of mitosis and meiosis 3. Support of spermatogenesis 4. Secretion of inhibin hormone 5. Secretion of androgen-binding protein 6. Secretion of Mullerian-Inhibiting factor (MIF) to descent of the Testis
What does the prostate gland do?
1. Produces prostate fluid, which is an alkaline solution (pH > 7 because vagina is very acidic) that contributes 20-30% of volume of semen 2. Secretion: seminalplasmin (antibody), which prevents urinary tract against infection
Urethra - three regions and what system are they a part of?
1. Prostatic urethra - urinary system 2. Membranous urethra - urinary and reproductive system 3. Penile urethra
What is the PSA? Why can PSA be used to detect the prostate cancer?
This is a blood test used to test for prostate cancer. The test measures the amount of prostate-specific antigen (PSA) is in your blood. PSA is a protein produced by both cancerous and noncancerous tissue in the prostate
Spermatogenesis process
Spermatogonium (stem cell, diploid) MITOSIS Primary spermatocyte (diploid) MEIOSIS 1 2nd spermatocyte (haploid) MEIOSIS 2 spermatid (immature sperm, haploid)
What is the function of the ejaculatory duct?
ejection of sperms
The organ that monitors and adjusts the composition of tubular fluid, recycled damaged spermatozoa, and is the site of sperm maturation is the a. ductus deferens b. rete testis c. seminal gland (seminal vesicle) d. epididymis e. prostate gland
epididymus
What is the function of interstitial cells?
produce androgens, which is testosterone
what is the vasectomy?
sperm are made in the testis. they pass through two tubes called the vas deferens to other glands and mix with seminal fluids to form semen. Vasectomy blocks each vas deferens and keeps sperm out of the seminal fluid. the sperm are absorbed by the body nstead of being ejaculated. without sperm, you ejaculate cacnnot cause pregnancy
What are the cells that are formed during spermatogenesis after mitosis?
spermatocyte
The process of spermatogenesis leads to the formation of _________?
spermatozoon (mature sperm)
What does FSH do?
stimulates testis and epididymis to produce sperm (spermatogenesis and spermiogenesis)
What does LH do?
stimulates testis to secrete sexual hormone called testosterone
What do interstitial cells secrete?
the hormone, testosterone
Spermatogenesis
the process fo immature sperm cells formation that takes place in the seminiferous tubules.
Spermatogenesis
the process that each spermatid matures into a single sperm cell, also called spermatozoon, happens in the epididymis
What is the function of the rate testis?
the resting/storage area for immature sperm
What is the Blood-testis barrier?
tight junctions between adjacent nurse cells form a blood-testis barrier (BTB), which prevents antibodies and other large molecules in the blood and intracellular fluid from getting to the germ cells.
Spermatogenesis process
Spermatid (immature, haploid) MATURES Mature sperm (spermatozoon, haploid)
What is the androgen-biding protein?
FSH stimulates the nurse cells of the testis to secrete ABP, which binds and accumulates testosterone in the seminiferous tubules and epididymis.
What is the process of testis descent?
Gonads and mesonepheric duct (2 months - embryo) Testis and epididymus (at 3rd month - fetus) Testis in Scrotum (at birth)
What is the Epididymis made up of and what are its functions?
It contains a head, body and tail that is 23 feet long, and is a coiled and twisted tubule. Functions: -Monitor and adjusts the composition of tubular fluid -Acts as recycling center for damaged spermatozoa -Stores spermatozoa and facilitates their functional maturation
What are the accessory glands?
Seminal vesicles Prostate gland Bulbourethral glands Semen Hormones
What is the major function of Mullerian-Inhibiting factor (MIC)?
a hormone secreted from testis. This causes atrophy of the paramesonephric duct on that side.
Bulbourethral glands secrete what?
a thick and alkaline mucus that helps to neutralize any urinary acids
Functions of the accessory glands of the male reproductive system include all of the following EXCEPT a. production of spermatozoa b. meeting the nutrient needs f spermatozoa for motility c. propelling spermatozoa and fluids along the reproductive tract d. producing buffers e. activating the spermatozoa
a. production of spermatozoa glands don't produce sperm, testis do
Seminal vesicles. What do they secrete?
contain 60% of the volume of semen. secretion: 1)Fructose 2) Prostaglandin, which stimulates smooth muscle contraction along the productive tract. 3) Fibrinogen, which will form a temporary clot within the vagina after ejaculation
Epididimys - what are the functions?
contains a head, body and tail that is 23 feet long, it is a coiled and twisted tubule. 1. Monitors and adjusts the composition of the tubular fluid 2. Acts as recycling center for damaged spermatozoa 3. Stores spermatozoa and facilitates their functional maturation
What does Inhibin do?
released from sustentacular cells of testis and functions a negative feedback to stop releasing of FSH