Female reproduction Flashcards
What are fallopian tubes also known as?
oviducts
What are the finger like projections that surround the opening of each fallopian tube called?
fimbriae
What are the external female genitalia?
mons pubis labia majora labia manora clitoris vestibule of the vagina vestibular glands
How many eggs do the ovaries contain at birth?
2-4 million
what are the primitive female germ cells called?
oogonia
During fetal life, what do all oogonia develop into?
primary oocytes
What are the daughter cells of the first meiotic division of the primary oocyte?
the secondary oocyte and the first polar body
Where does the secondary oocyte divide to from the ovum and the second polar body?
the the fallopian tube after fertilisation
How many ova can each primary oocyte produce?
only one
What do the ovarian follicles begin as?
primordial follicles
Describe a primordial follicle
one primary oocyte surrounded by a single layer of granulosa cells
What separates the granulosa cells from the oocyte?
the zona pellucida
What is the role of the zona pellucida in fertilisation?
the zona pellucida contains glycoproteins that bind the sperm to the egg
At the beginning of each menstrual cycle, how many antral follicles develop into larger antral follicles?
10 to 25
At about a week into the cycle, only one of the larger antral follicles continues to develop. What is this follicle referred to as?
the dominant follicle
What is the degenerative process called by which the non-dominant follicles degenerate?
atresia
What is the mature follicle referred to as?
the graafian follicle
At what say does ovulation usually occur in the menstrual cycle?
day 14
What is the most common cause of multiple births?
more than one egg is ovulated
After the mature follicle has undergone ovulation, what does it become?
the corpus luteum
Which two phases can we split the ovarian menstrual cycle into?
follicular phase- mature follicle and secondary oocyte develops
luteal phase- beginning after ovulation and lasting until the death of the corpus luteum
Describe the pattern of FSH secretion throughout the menstrual cycle
FSH increases at the start the steadily decreases throughout the remainder of the cycle except for a small mid peak
Describe the pattern in LH secretion throughout the menstrual cycle
Constant during most of the follicular phase
large midcycle increase called the LH surge
followed by a rapid decrease and slow decline in the luteal phase
Why does oestrogen increase rapidly during the second week of the menstrual cycle?
the dominant ovarian follicle grows and secretes more oestrogen
What is the second peak of eostrogen in the menstrual cycle a result of?
secretion by the corpus luteum
Describe the pattern of progesterone levels in the menstrual cycle. Why does progesterone increase?
very low progesterone during the follicular phase
soon after ovulation the corpus luteum releases large amounts of progesterone
Which phase is inhibin high in?
the luteal phase. Decreases as the corpus luteum degenerates
What does the corpus luteum secrete?
oestrogen
progesterone
inhibin
Which cell type does FSH act on?
granulosa cells
What effect does FSH have on granulosa cells?
causes them to proliferate
causes them to produce oestrogen
What cell type does LH act on?
theca cells
What effect does LH have on theca cells?
causes them to proliferate
causes them to synthesise androgens
What is the primary cause of ovulation?
the LH surge
What does LH cause theca cells to synthesise?
androgens
What happens to the androgens synthesised in the theca cells?
androgens diffuse into granulosa cells and are converted to oestrogen
Describe the negative feedback in the menstrual cycle
Oestrogen- acts on hypothalamus and anterior pituitary
inhibin- acts on anterior pituitary (mainly inhibits FSH)
What day in the menstrual cycle is the first day of menstrual flow?
day 1
How long does the menstrual phase usually last ?
3-5 days
What is degenerating in the menstrual phase?
the endometrium
What uterine phase comes after the menstrual phase?
the proliferative phase
What regenerates in the proliferative phase of the menstrual cycle?
the endometrium
What hormone is the proliferative phase under the influence of?
oestrogen
What phase follows the proliferative phase of the menstrual cycle?
the secretory phase
Which ovarian phase is the same as the uterine secretory phase?
the luteal phase
Describe what happens in the secretory phase of the menstrual cycle?
the endometrium secretes glycogen and glycoproteins
What hormones influence the secretory phase?
oestrogen and progesterone
What is the underlying uterine smooth muscle referred to as?
the myometrium
