Physiology of the Reproductive System Flashcards
Name the components of the male reproductive system.
- Bulbourethral gland
- Prostate gland
- Seminal vesicle
- Ductus deferens
- Epididymis
- Testis
- Scrotum
Where is the seminal fluid located?
- 5% in the bulbourethral glands
- 30% in the prostate gland
- 60% in the seminal vesicles
How much semen does the male reproductive system contain?
2-5ml
How many sperm does the male reproductive system contain?
20-200million sperm per ml of semen
Where are sperm produced?
Seminiferous tubules of the testis
What cells are sperm produced from?
Spermatogonium which produce spermatocytes which undergo meiosis to produce immature spermatids
What cells support and give nutrition to developing gametes in the male?
Sertoli cells
What are the features of the seminiferous tubules?
- 150 µm diameter, 80 cm long
- Total 300-900 m
- Join at rete testis
What is the role of the epididymis?
Sperm storage
What route do sperm take during ejaculation?
- Vas deferens (ductus deferens)
- Seminal vesicles
- Prostate
- Bulbourethral glands
- Urethra
What are the roles of the sertoli cells?
- support sperm producing cell
- produce inhibin
Briefly describe the process of sperm production through to ejacualtion
Production 75 days in seminiferous tubules
- Spermatocytogenesis
- Meiosis
- Spermiogenesis
Storage 15 days in epididymis
-Become motile
Sexual intercourse in vagina
- Ejaculation
- Capacitation
What is the counter current heat exchange of the male reproductive system?
- Arterial blood going to the testis enters a dense network of capillaries coming from the testis and epididymis before reaching the spermatic cord
- The arterial blood is cooled by the venous blood
- Helps maintain a constant testicular temperature
What factors affect spermatogenesis?
- Testis temperature
- Endocrine
- Loss of blood-testis barrier
- Immunological reactions
- Environment
- Medication
What endocrine causes can affect spermatogenesis?
- Reduction in gonadotrophins and androgens
- Anabolic steroids
What environmental factors can affect spermatogenesis?
- Occupation e.g. car industry, welders, plastic manufacture, pesticide sprayer
- Radiation
- Smoking, alcohol
What medications can affect spermatogenesis?
- Some anti-hypertensives and anti-depressants
- Chemotherapy
What testis temperature change can affect spermatogenesis?
- Should be 2C below body temperature
- Hyperthermia, mumps, viral and other infections
What are the targets for androgens in males?
- Systemic
- CNS (aggressive behaviour)
- Hypothalamus and anterior pituitary
- Penis (erective, copulatory and ejaculatory effectiveness)
- Striated muscle
- Prostate and seminal vesicles
- Testis (spermatogenesis)
What system effects can androgens have in males?
- Deepening voice
- Male body hair
- Increased sebaceous gland activity
- Protein anabolism
What is the menstrual cycle?
- A regular monthly cycle which occurs in females
- Can be sexually active at any time even if not ovulating
- If no conception occurs then the endometrium is shed as a period
What ae the components of the female ovary?
- Blood vessels
- Stroma
- Follicles (primordial, growing, vesicular, mature grafiaan)
- Corpus lutum
- Corpus albicans
What hormone change occurs shortly before ovulation?
LH surge about 36 hours prior to ovulation
Briefly describe the hormonal changes which occur during a menstrual cycle.
- Cycle usually 28-35 days with bleeding (period) for the first 5-7 days
- LH surge about day 13/14 as ovulation occurs
- FSH has a small surge about day 13/14 when ovulation occurs
- Progesterone levels increase during the luteal phase and fall again as the corpus luteum becomes the corpus albicans
- Oestrogen increases as ovulation takes place
