Ch9+Ch10 Reproductive Organs and Hormonal Control: Female Flashcards
What is the oviduct?
The oviduct is the site of fertilisation.
What do the ovaries do?
The ovaries produce and store eggs (ova).
Where are ova produced?
Ova are produced from germline cells in the ovaries.
What is each ova surrounded by and why?
Each ova is surrounded by a follicle which protects it and releases hormones.
When are ova released and where?
A mature ova is released each month into the oviduct where fertilisation with a sperm may take place.
What hormone does the maturing follicle release?
The maturing follicle releases estrogen.
After ovulation, the follicle develops into a corpeus luteum. What hormone does it secrete?
The corpeus luteum secretes progesterone.
What two phases does the menstrual cycle consist of?
The menstrual cycle consists of two phases:
- Follicular phase
- Luteal phase
At the onset of puberty, what hormone does the hypothalamus secrete?
At the onset of puberty, the hypothalamus secretes a releaser hormone which targets the pituitary gland.
How does the pituitary gland respond to the releaser hormone?
The pituitary gland releases two hormones:
- FSH (Follicle stimulating hormone)
- LH (luteinising hormone)
What does FSH do?
FSH stimulates the maturation of the follicle.
It also stimulates the ovary tissue to secrete oestrogen.
What does LH do?
LH stimulates ovulation.
Also stimulates the development of the corpeus luteum from the follicle.
Name the ovarian hormones
Oestrogen and progesterone
What are the four roles of oestrogen?
Oestrogen has four roles:
- Stimulates proliferation (cell division) of the endometrium. This makes it spongy and thick, ready for implantation.
- Oestrogen affects the consistency of mucus in the in the cervix making it easier for sperm to penetrate.
- Oestrogen stimulates a surge in LH levels causing ovulation.
- When oestrogen levels increase they inhibit (prevent) the pituitary from releasing FSH. This stops any more follicles developing.
What are the two roles of progesterone?
Progesterone has two roles:
- Vascularisation – the further development of the
endometrium ready for implantation. - Negative feedback. As the progesterone levels increase it inhibits the release of LH and FSH from the pituitary. The lack of LH causes the corpus luteum to degenerate causing a decrease in progesterone levels triggering menstruation. This is an example of negative feedback.
