The Male Reproductive System Flashcards
What is the main role of the penis?
- Passes urine out of the body
- Becomes erect to allow intercourse and passes semen into the vagina
What is the main role of the testes?
- Spermatozoa are produced in the seminiferous tubules and mature as they pass through the long and convoluted epididymis, where they are stored.
- Temperature control.
- Testosterone release - secondary sexual characteristics
What is the main role of the the Vas Deferens
- Stores and conveys spermatozoa
- Passes upwards from testis through the inguinal canal and ascends medically towards the posterior wall f the bladder where it is joined by the ejaculatory duct.
What is the main role of the urethra
- Common pathway for urine and semen
- Mucous-like secretions enter urethra during intercourse to neutralise urine residue
What is the main role of the scrotum
- A pouch divided into 2 compartments each containing one testis, one epididymis and the testicular end of the spermatic cord.
- provides protection and temperature control
What is the main role of the epididymis
- Spermatozoa are matured and stored in the tail of the epididymus.
- Continuous with Vas Deferens
Define the function of the male reproductive system
- Production of androgens (testosterone)
- Production, storage and nourishment of male gametes
- Introduction of male gametes into female reproductive tract
Trace the path of sperm from the site of production to the outside
1) TESTIS - site of production is the seminiferous tubules
2) EPIDIDYMUS - sperm migrate from the tubules to the epididymus where it is stored and matured
3) VAS DEFERENS - the ejaculation process begins as the penis fills with blood and becomes erect, mature sperm travel through the vas Deferens which propels sperm forward through smooth muscle contraction.
4) AMPULLA - sperm arrive first at the ampulla where secretions from seminal vesicles are added
5) EJACULATORY DUCTS - seminal fluids propelled through these ducts towards the urethra passing the prostate gland where milky fluid is added to form semen
6) URETHRA - Semen is ejaculated through the far end of the urethra
Define the location of the prostate and and describe its function
- Location - it lies in the pelvic cavity in front of the rectum and behind the symphysis pubis, surrounding the first part of the urethra
- Function - it secreted a thin milky fluid that makes up about 30% of semen and gives it its milky appearance. Contains a clotting enzyme which thickens the semen in the vagina increasing likelihood of retention.
Explain the role of hormones in the development of seconded sexual characteristics and the male reproductive system
- LUTEINISING HORMONE - stimulates the interstitial cells of the testes to increase the production of:
- TESTOSTERONE - influenced the development of the body to sexual maturity. The changes that occur at puberty are: muscle growth, enlargement of larynx (voice drops), public and bodily hair, maturation of seminiferous tubules, production of spermatozoa, enlargement of penis, scrotum and prostate.
Explain the role of negative feedback in the control of hormone secretion
- If there is a low level of hormone in the blood supplying the hypothalamus; it produces the appropriate releasing hormone.
- This stimulates the target gland to produce and release its hormone.
- As a result, the blood level of that hormone rises and inhibits the secretion of releasing factor by the hypothalamus.
Describe the basic principles behind IVF treatment
- Injection of a single sperm directly into an egg.
- Fertilised egg is then transferred to woman’s womb.
Which cells secrete inhibin and androgen-binding hormone?
Sertoli cells
Which cells secrete testosterone?
Leydig cells
What is mitosis?
The division of a parent cell into 2 daughter cells that are genetically identical to parent cell
