Basic Male and Female Physiology Flashcards
What components of the male reproductive system contribute to volume of semen and what do they contribute?
Bulbourethral gland - 5% of seminal fluid
Prostate gland - 30% of seminal fluid
Seminal vesicle - 60% of seminal fluid
What is the male reproductive system composed of?
Bulbourethral gland Prostate gland Seminal vesicle Ductus deferens Epididymis Testes Scrotum Penis
Where is sperm produced?
Seminiferous tubule
How is sperm carried from the seminiferous tubules to the epididymis for storage?
Via efferent ductules
What components of the male reproductive system are involved in ejaculation?
Vas deferens Seminal vesicles Prostate Bulbourethral glands Urethra
What are the functions of Sertoli cells?
Form blood-testis barrier
Isolate haploid secondary spermatocytes, spermatids and spermatozoa from the immune system
Physical movement of developing sperm towards the lumen
Provision of nutrients to sperm
Removal of wastes from developing sperm
Removal of excess cytoplasm following cell divisions
Support for permeation
How long does the production of sperm take?
Around 75 days
What are the stages involved in sperm production?
Spermatocytogenesis
Meiosis
Spermiogenesis
How long are sperm stored in the epididymis for?
15 days
What is the counter-current heat exchange?
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 which helps to maintain a constant testicular temperature
How many degrees below body temperature should testis temperature be?
2
What can affect testis temperature?
Hyperthermia Mumps Viral infections Other infections Endocrine changes Loss of blood-testis barrier Immunological reactions Environment Medications
What endocrine changes can affect testis temperature?
Reduction in gonadotrophin and androgens
Anabolic steroids
What kind of damage can cause loss of the blood-testis barrier?
Physical damage
What medications can affect testis temperature?
Some anti-hypertensives and anti-depressants
Chemotherapy
What are the targets of androgens?
CNS Anterior pituitary Hypothalamus Penis Striated muscle Prostate and seminal vesicles Testis
What are the systemic effects of androgens?
Deepening voice
Male body hair
Increased sebaceous gland activity
Protein anabolism
What are the typical hormone levels of; LH FSH Testosterone Inhibin-B
LH 1-8 U/L
FSH 1-11 U/L
Testosterone 9-33 nmol/L
Inhibin-B - 140-220pg/mL
What are the differences between female mammals and female humans in reproduction?
Female humans have;
Regular monthly menstrual cycle
Sexually active at any time, even if not ovulating
Endometrium shed if there is no conception - period
What does FSH stimulate follicles to do?
To develop into dominant follicles, producing positive feedback to the pituitary to continue FSH production
Mid menstrual cycle there is a surge in what hormone to stimulate ovulation?
Luteal hormone
Where are oestrogen and progesterone produced?
By the ovary
What does the corpus luteum produce and what does this cause?
Corpus luteum produces progesterone to make the endometrium receptive to a fertilised egg
What effect does low oestrogen concentration have?
Negative feedback effect, high oestrogen concentration produces a positive feedback effect
Oestrogen produces feedback effect via what?
Hypothalamus and anterior pituitary
What is the effect of oestrogen and progesterone on menstrual symptoms? e.g. sore breasts, mood fluctuations, fluid retention
Oestrogenen relieve menstrual discomfort, progesterone will worsen it
What are the main female reproductive hormones?
GnRH LH FSH Oestradiol Progesterone
Where is GnRH produced and what does it stimulate?
Produced from hypothalamus
Stimulates LH and FSH secretion from the anterior pituitary
Where is LH produced and what are its actions?
Produced from the anterior pituitary
Maintains dominant follicle, induces follicular maturation and ovulation and stimulates corpus luteum functions
Where is FSH produced and what are its functions?
Produced from the anterior pituitary
Stimulates follicular recruitment and development
Where is oestradiol produced and what does it stimulate?
Produced from the granulosa cells
Support female secondary sexual characteristics and reproductive organs, negative feedback control of LH and GnRH (except in late follicular phase)
At what phase does estradiol no support the negative feedback control of LH and GnRH?
In the late follicular phase where positive control of LH surges and stimulates the proliferative endometrium, at this point there is negative control of FSH
Where is progesterone produced and what are its functions?
Produced from corpus luteum
Maintains secondary endometrium, negative feedback control of HPO
What are the targets of oestrogens?
CNS Anterior pituitary Hypothalamus Fat distribution Ovary Mammary gland Bone maturation and turnover Cervix, vagina, Fallopian tubes and uterus
What are the systemic effects of oestrogens?
Protein metabolism Carbohydrate metabolism Lipid metabolism Water and electrolyte balance Blood clotting
