Hormones B3 Flashcards
What are the 4 sex hormones in the menstrual cycle and what are their functions?
Oestrogen which stimulates the uterus lining growth. Progesterone which maintains the lining of the uterus. LH which stimulate the release of mature egg on day 14 (ovulation). FSH which stimulates the release of mature eggs in ovaries.
What is the role of testosterone and where is it produced?
Testosterone is the main sex hormone, it’s produced in the tested and it stimulates sperm production and is important for the development of the male reproductive system.
Which hormone maintains the lining of the uterus?
Progesterone
Which hormone stimulates the egg follicle to mature?
FSH (Follicle stimulating hormone)
Which hormone stimulates the egg to be released around day 14 (ovulation)?
LH (Luteinising hormone)
Which hormone stimulates the uterus lining to develop?
Oestrogen
Which organ are both luteinising hormone and follicle stimulating hormone released from?
Pituitary gland
What happens at stage 1 of the menstrual cycle?
Menstruation, which is the period of bleeding due to the breakdown of the uterus lining. This lasts 4 days.
What happens at stage 2 of the menstrual cycle?
The uterus lining starts to build up again, its role is to prepare the uterus lining for a fertilised egg. This lasts 10 days.
What happens at stage 3 of the menstrual cycle?
Ovulation, which is when the egg is released from the ovaries. This lasts 1 day.
What happens at stage 4 of the menstrual cycle?
The uterus lining is maintained.
What would happen if there was no fertilised egg at the uterus at the end of the menstrual cycle?
The uterus wall begins to breakdown and the process is repeated once again.
What would happen if there was a fertilised egg at the uterus at the end of the menstrual cycle?
The fertilised egg would implant into the uterus lining and would slowly develop into a foetus. The menstrual cycle would stop because there would be no need for it.
What is puberty and an example of it?
Puberty is the period in which adolescents start to develop sexual characteristics such as facial hair in men (by testosterone) and breast development in women (by oestrogen)
Describe the process of the menstrual cycle.
Firstly, the women goes through menstruation which is the period of bleeding as the uterus lining breaks down. This lasts 4 days. Then the uterus lining starts to build up again due to oestrogen. This lasts 10 days. Then ovulation begins, this is where eggs are released from the ovaries into the uterus. Finally the maintaining of the uterus lining.
How long is the average menstrual cycle?
28 days
What is infertility?
Infertility is when people cannot get pregnant or have kids.
What is the simple way of treating infertility?
Infertile women have low levels of FSH, meaning their eggs can’t mature, so they are given FSH in the form of a pill and then later given LH to stimulate ovulation (release of egg)
Describe the process of IVF being given to a women.
Women are given FSH and LH to stimulate eggs maturing and ovulation. Eggs are then collected from women’s ovaries and fertilised by the sperm of the father. The fertilised eggs are then placed into an incubator and are left to grow into embryos. Once the embryos have grown, they will be taken out and inserted into the mother’s uterus. The embryos will finally develop into a foetus.
What could a male do if he has a low sperm count and wants to have a baby?
A man can undergo ICSI, which is where sperm is injected into the egg by a tiny needle.
What are the pros of IVF?
Infertile couples can have babies.
What are the cons of IVF?
IVF doesn’t always work so it can be stressful, emotionally upsetting. It can also cause the mother abdominal pain and vomiting. Also when multiple embryos are inserted into the uterus it can lead to multiple births, which puts mothers at a higher risk of a miscarriage.
Why can IVF be unethical?
IVF can be unethical as it puts unused embryos in the uterus which are eventually destroyed although they had the potential for human life. It can also lead to ‘designer babies’ where parents could select the embryos with certain traits.
Why are embryos kept in an incubator at a lab?
Embryos are kept in an incubator to provide the optimum temperature for enzymes and thus cell growth.
