Reproduction - Female Flashcards
What is the function of the female reproductive system?
- produce gametes
- transport gametes for fertilisation
- provide a receptacle for fertilisation
- embryogenesis and fetal development
- give birth
- nurture the newborn
What are the two main areas of the ovary?
- ovarian medulla (inner, blood supply enters then branches out)
- ovarian cortex (outer, most process occur here)
What cell types are present in a follicle?
- thecal cells - outer
- granulosa cells - inner
Development of a follicle
Primary follicle
Secondary follicle (first meiotic division completed)
Graafian follicle
What do ovarian follicles do?
- house and nurture oocytes
- secretes estradiol and inhibit for the first half of the cycle
What is the Corpus luteum formed from?
Thecal and granulosa cells of the follicle
What does the Corpus luteum regress to?
Corpus albicans
Regresses after 10-12 days
Where does fertilisation normally take place?
Ampulla of the uterine tube
What is the isthmus?
The narrow part of the uterine tube
What are the types of cells found in the uterine tube?
Ciliated: transports egg and embryo
Secretory: secrete early nourishment for a newly formed embryo
What parts make up the uterus?
Myometrium: outer muscle wall
Endometrium: inner lining
What are the characteristics of the endometrium?
- rich blood supply
- highly glandular
Why are changes in the endometrium cyclic?
Because is require a metabolic investment to maintain
What type of epithelium is found in the uterus?
Simple columnar (ciliated) Secretory cells
What are the stages of the menstrual cycle?
Menstrual
Proliferative
Secretory
Premenstrual
Menstrual phase
Functional layer breaks down
Glands break down
Edema (fluid)
Proliferative phase
Functional layer increasing in height (proliferating)
Small glands rounded in shape
Secretory phase
Functional layer well built up
Glands are very long and elongated
Lots of secretory product
Highly vascular
Premenstrual phase
Endometrial ischemia (interrupted blood flow)
What is the effect of taking the contraceptive pill?
Leads to constant, relatively high levels of progesterone and estrogen in the blood
Contraceptive pill: what effects do relatively high levels of progesterone and estrogen have?
Exerts negative feedback on the hypothalamus and pituitary decreasing GnRH, LH and FSH
What effect does the combined pill have on follicular development?
Follicular development is inhibited
What happens when a woman takes the placebo pill?
Blood levels of progesterone and estrogen decline
How long after starting the placebo pills would you expect menstruation to start?
2 days, it takes that long for blood levels to fall sufficiently for menstruation to start
What are the two type of epithelium found in the cervix?
- simple columnar (uterine side)
- stratified squamous (vaginal side)
Progesterone cervical mucus
Sticky and clumpy, prevents sperm and pathogens from going into the uterus
Estrogen cervical mucus
Viscous and thin, easy for spero to pass through
What type of epithelium does the vagina contain?
Stratified squamous
What do specialised epithelial cells in the vagina do?
Accumulate glycogen which:
- converted to lactic acid
- acidic pH
- inhibits pathogen growth
Follicular phase
1-12
Estradiol
Negative
Menstrual and proliferar stages
Ovulation
12-14 Estradiol Positive Proliferano phase Thin and watery (estrogen)
Luteal phase
14-28 Progesterone and estradiol Negative Secretory and premenstrual phases Thick and viscous (progesterone)
What effect does inhibin have?
- exerts negative feedback on the secretion of FSH
- decreases FSH
- so that all but the dominant follicle, which has the most FSH receptors, degenerate
Homologous nature of male and female reproductive systems
- an embryo in the early stages (weeks 5-6) has reproductive structures, ducts and Honda that can develop into male or female system
- once the genes determining sex are expressed, the appropriate structures will remain and the others will degenerate, and the primitive gonads will develop into ovaries or testes
Examples of homologous nature of reproductive system
Urogenital fold: a structure that becomes the spongy urethra in the males of the labia minora in the females
Labioscrotal area: a structure that becomes the scrotum in the males or the labia majora in the females
What causes positive feedback?
Rising estradiol levels driven by the dominant follicle
What occurs because of the positive feedback?
LH surge and smaller spike of FHS
What are the hormone levels in the luteal phase?
- increasing progesterone from Corpus luteum
- estradiol levels high compared to early follicular phase
- LH and FSH levels low due to negative feedback
What stages of meiosis does oogenesis pause in?
Prophase I
Metaphase II
