UNIT 2 - KA3
No description yet. This curated deck is ready for daily study.
Card preview (24)
Why do men show continuous fertility
• in males there is a relatively constant level of FSH and LH secreted in the bloodstream. Therefore a steady quantity of testosterone is secreted and steady quantity of sperm produced. As a result, males are continuously fertile
What do men continuously produce which shows continuous fertility
Men continuously produced sperm in their testes so show continuous fertility
Why do women show cyclical fertility
• in females the interplay of pituitary and ovarian hormones results in the period of fertility being 1 - 2 days after ovulation. For this reason females fertility is described as being cyclical
What are the two indicators of a women’s fertile period
• temperature • cervical mucus
When does the woman’s body temperature rise
Approximately one day after the luteal surge that triggers ovulation the woman’s body temperature rises by around 0.5 degrees Celsius and remains at this level throughout the luteal phase of the cycle
How long does the period of fertility last
The period of fertility lasts for the first 1-2 days
When does the infertile phase resume
The infertile phase is resumed on average, on the third daily recording of the higher temperature by this time the egg not fertilised would have disintegrated
What consistency is the cervical mucus
The cervical mucus secreted into the vagina during the fertile period is thin and watery
What does thin and watery mucus allow
This allows easy access of sperm into the female reproductive system
What happens to the mucus after ovulation
After ovulation progesterone causes the mucus to gradually increase in viscosity
Identification of the fertile period
A woman’s body temperature rises by around 0.5 degrees Celsius after ovulation and her cervical mucus becomes thin and watery
What are infertility treatments and contraception based on
Infertility treatments and contraception are based on the biology of fertility
What can the pituitary gland fail to secrete
Sometimes there is a failure of the pituitary gland to secrete adequate FSH or LH
Ovulation can be stimulated by :
• drugs that mimic the normal action of FSH and LH • drugs that prevent the negative feedback effect of oestrogen on FSH secretion
What can the drugs that mimic the normal action of FSH and LH do
These drugs can be so effective that they can bring about ‘super ovulation’ which can lead to multiple births
What are the two things super ovulation can do
Super ovulation can lead to multiple births. Super ovulation can be used to collect ova for IVF
What type of means does AI introduce semen
A.I is when semen is introduced by means other than sexual intercourse
What procedure is used during artificial insemination
Several samples of semen are collected over a period of time
When is artificial insemination particularly useful
Artificial insemination is particularly useful where the the male has a low sperm count
If a partner is sterile how can artificial insemination work
If a Partner is sterile a donor may be used to provide semen
Summarise artificial insemination
Several samples of semen are collected over a period of time. Artificial insemination is particularly useful when a male has a low sperm count. If a partner is sterile a donor may be used to provide semen
What is ICSI
Inta-cytoplasmic sperm injection
Under what conditions can ICSI be used
If mature sperm are defective or very low in number ICSI can be used
What procedure takes place during ICSI
The head of the sperm is drawn into a needle and injected directly into the egg to achieve fertilisation