Reproductive physiology Flashcards
Define biological sex
Gender Male= XY and Female =XX
How does sexual reproduction differ from other form of reproduction (eg asexual)
Sexual reproduction requires intercourse and it produces offspring that is genetically different from both parents.
What system is part of the pleasure and reward system associated with sexual intercourse.
Mesolimbic dopaminergic system
What is the most important sexual organ and why
The brain as activation of pleasure pathways keeps humans procreating and ensure human life. Also gametogenesis is regulated by the HPG axis. (CNS also involved in physical arousal).
What enzyme inhibits penile erection.
phosodiesterase deactivates cyclic GMP. Note Viagra inhibits this enzyme.
Which nerve forms the afferent pathway involved in penile erection
pudendal nerve
What role does the parasympathetic system play in arousal?
Vasodilation, mediated by NO, of the pudendal artery causing an erection.
Where does spermatogenesis occur?
Seminiferous tubules in the testes
What endocrine role do leydig cells have?
They produce testosterone when stimulated by LH. This encourages the differentiation of sperm.
What is the role of Sertoli cells?
Sertoli cells provide physical and nutritional support to developing sperm. They are FSH responsive.
What is the path of sperm during ejaculation?
Sperm are stored prior to ejacualtion in the epididymis,then are released into the vas deferens, during which time various secretions are mixed with the sperm to become seminal fluid. The ejaculate leaves via the urethra.
Draw a diagram of an ovary
please google, I’m cheap.
What is the role of the fallopian tube in reproduction
It transports the oocyte from the ovary to the uterus. The medial third is often the sit of fertilisation.
Which cells in the ovary produce which hormones
Granulosa cells produce Oestrogen and inhibin ( stimulated by FSH)
Thecal cells produce progesterone (stimulated by LH) in
May need to edit.
Follicular phase and luteal phase are part of which cycle?
Ovarian cycle.
Follicular=14 days
Ovaulation
luteal= 14 days
What are the phases of the endometrial cycle and their lengths?
menstrual phase= 1-5 day (5)
Repair and proliferative= day 5-14 (9)
secretory phase= day 15-28 (13)
What obseration changes at ovulation
increased body temperature.
What endocrinological change stimulates ovulation?
continual high levels of oestrogen cause a change to postive feedback on LH causing an LH surge in the late follicular phase.
Draw the hormone graph
which phase is controlled by an increase in progesterone?
The secretory phase. Progesterone from the corpus luteum stimulates production of nutrients, epithelial gland thickening, increased vascularisation.
What is different between the genders for gametogensis?
Females are born with total number primordial follicles they will ever have. The quality of of oocytes decreases at 45 years old and menopause indicates no more eggs. Eggs at ovulation are at the 2n meiosis metaphase II (previously paused at meiosis prophase I. where as males can produce sperm their whole life although they may decrease in quality.
What causes capacitation and what are its effects?
Progesterone released from the oocyte.
It increases sperm motility and acts to increase chemotaxis
What reaction prevents polyspermy?
Acrosome reaction
What does calcium influx cause during fertilisation?
Resuming of meiosis for the oocyte and completion of oogenesis releasing the 2nd polar body.
