B11b Hormones in human reproduction Flashcards
Name the main female reproductive hormone
Oestrogen
Name the gland that releases oestrogen
Ovary
After puberty eggs being to mature and one is released
approximately every 28 days,
What is the release of an egg called?
Ovulation
Name the main male reproductive hormone
Testosterone
Name the gland that releases testosterone
Testes
What effect does testosterone have on the testis?
Stimulate sperm production
Give two effects of follicle stimulating hormone (FSH)
Causes an egg to mature
Stimulates the ovary to release oestrogen
What effect does luteinising hormone (LH) have on the body?
Causes ovulation (release of an egg from the ovary)
What effect do oestrogen and progesterone have on the uterus?
Maintains the uterus lining
What do oral contraceptives contain?
Hormones that inhibit FSH production so no eggs mature
How does slow release progesterone prevent pregnancy?
Inhibits an egg maturing and prevents the release of an egg from the ovary
How can slow release progesterone be administered?
Injection or implant or skin patch
Name 2 types of barrier contraception
Condom
Diaphragm
How do barrier contraceptives prevent pregnancy?
Prevent sperm reaching the egg
How do intrauterine devices prevent pregnancy?
Prevent the implantation of an embryo
Prevents release a hormone
How so spermicides prevent pregnancy?
Kill or disable the sperm
Males and females can be sterilised.
What does this mean?
Surgical method to prevent pregnancy
Males - sperm ducts are tied or cut
Female - oviducts are tied
Give natural way of controlling pregnancy
Abstaining from intercourse when an egg may be in the oviduct
Why might a female be treated with FSH and LH?
Increase fertility
Give an outline of IVF treatment
Mother given FSH and L to stimulate the maturation of several eggs
Eggs are collected from the mother and fertilised by sperm from the father in the laboratory
The fertilised eggs develop into embryos
One or two embryos are inserted into the mother’s uterus
What are the disadvantages of IVF treatment?
Emotionally and physically stressful
Success rates are not high
Can lead to multiple births which are a risk to both babies and the mother
What is the function of reproductive hormones during puberty?
Males - development of secondary sexual characteristics
Females - development of secondary sexual characteristics and the maturation of eggs.
Describe the events of the menstrual cycle
Uterus lining thickens and eggs begin to mature in the ovaries.
An egg is released from one of the ovaries
Uterus lining remains thick
If the egg is fertilised, pregnancy may occur
If not, both the egg and uterus lining are shed during menstruation
What is ovulation?
Release of an egg from the ovary
Name the gland that releases FSH and LH
Pituitary gland
What effect does oestrogen have in the menstrual cycle?
Causes the uterus lining to thicken
Stimulates the production of LH
Inhibits the release of FSH
What is contraception?
Method of preventing pregnancy
What are the advantages of IVF?
Allows infertile couples to have children
Can store a woman’s eggs for later
What is negative feedback? (Higher)
Type of control where the body responds to an increase r decrease in a factor by returning it to the optimum level
