Topic 7 - animal Coordidination, Control And Homeostasis Flashcards
What are the 4 key hormones that are involved in the menstrual cycle?
FSH, LH, progesterone, oestrogen
What does FSH do?
follicle stimulation hormone causes a follicle to mature in the ovary
What does LH do?
Luteinising hormone causes an egg to be released (ovulation)
What does oestrogen and progesterone do?
maintaining the uterus lining in case an egg is implanted
What is the first stage (day 1) of the menstrual cycle?
The lining of the uterus is broken down and released through the vagina with blood
What is the second stage (day 4) of the menstrual cycle?
The lining of the uterus starts building up again until day 14 so it can supply nutrients
What is the third stage (day 14) of the menstrual cycle?
An egg is released from the ovary (ovulation) and this is the most fertile stage
What is the uterus lining called?
The endometrium
Why does the uterus lining thicken?
It needs to provide nutrients and support for the fertilised egg
Why is the follicle important?
It contains the egg until it matures
Where is FSH and LH secreted from?
The pituitary gland
Where is oestrogen secreted from?
The ovaries
Where is progesterone secreted from?
The corpus luteum
What happens at the peak of LH and what does it form?
Ovulation and results in the form of the corpus luteum
What does progesterone inhibit?
FSH and LH production
What does oestrogen inhibit?
FSH and LH production in the pituitary gland
What happens if fertilisation doesn’t happen (in terms of hormones)?
Progesterone levels drop and menstruation occurs
What does oestrogen stimulate?
The uterus to develop a lining called the endometrium
What does FSH stimulate?
Egg maturation in the follicles of the ovary
What is clomifene therapy?
Causes more FSH and LH to be released by the body to stimulate ovulation to improve chances of becoming pregnant
What is IVF?
Assisted reproductive therapy, IVF stands for in vitro fertilisation
Briefly describe the 5 stages of IVF
-inject woman with LH
-harvest eggs using syringe and put on Petri dish
-incubate eggs at 37 degrees
-ensure all cells have multiplied and have become embryos
-implant healthiest embryo in the uterus
-give birth to a baby
Why might some women be infertile?
Oviducts might be blocked, woman may not produce eggs
What is the target organ of clomifene?
The pituitary gland