Controlling Fertility

Question 1

Fertility

Answer 1

Ability to produce offspring

Question 2

Continuous Fertility

Answer 2

Male

Levels of FSH and ICSE are kept relatively constant through negative feedback. As a result, sperm are produced continually.

Question 3

Cyclical Fertility

Answer 3

In women, fertility is cyclical. Levels of oestrogen and progesterone, FSH and LH fluctuate. As a result women are only fertile for small number of days before and after ovulation during each menstrual cycle.

Question 4

Ovulation

Answer 4

Release of an ovum from one of ovaries

Question 5

Identifying women’s fertile period

Answer 5

body temperature - increases after ovulation

cervical mucus - clearer, wetter and more slippery

timing of menstrual cycle - ovulation occurs 10 to 16 dayys before start of period

Question 6

stimulating ovulation

Answer 6

Prevent negative feedback effect of oestrogen on FSH

Mimic normal action FSH and LH, stimulating ovulation

Question 7

Artificial stimulation ovulation can lead to….

Answer 7

multiple births - super ovulation

can be used un IVF too to help collect ova as several need to be collected

Question 8

AI may be useful when?

Answer 8

man has a low sperm count

couple are unable to have vaginal intercourse

condition means couple need help to conceive

when donor sperm is being used by same-sex couple or when a man in mixed-sex couple is sterile

Question 9

Sperm sample AI

Answer 9

A sample of sperm is treated to remove dead sperm, slow sperm and impurities. A concentrated sample of healthy sperm is then passed through a catheter into the uterus. A sperm donor may also be used in artificial insemination in cases of a male being sterile.

Question 10

Intra cytoplasmic sperm injection used when

Answer 10

sperm count low

mature sperm are abnormally shaped or don’t move normally

sperm needs to be surgically removed

frozen sperm has reduced quality being used

Question 11

ICSI sperm sample

Answer 11

Sperm collected and head of sperm drawn into needle and injected directly into egg in order to increase chances of fertilisation.

Question 12

IVF can be used when

Answer 12

issues with sperm quality

womens blocked oviduct

where one or both partners may pass genetic condition

donor or sperm egg being used

Question 13

IVF

Answer 13

Involves one or more eggs being removed from woman’s ovaries. These are then fertilised with sperm in laboratory

Question 14

IVF steps

Answer 14

1. the mother is given FSH and LH to stimulate maturation of several eggs in ovary
2. egg are collected from mother and fertilised with sperm from father in culture dish in lab
3. fertilised eggare incubated until they develop into embryos
4. at stage when tiny balls of at least 8 cells, one or 2 embryos inserted into other’s uterus

Question 15

develop of what has allowed IVF treatments to develop further

Answer 15

microscopy techniques

Question 16

Pre-inplantation genetic diagnosis (PGD)

Answer 16

IVF is used in conjunction with PGD where one or more parents at risk of serious inherited disease to their children. PGD can be used to check single gene disorders and chromosome abnormalities in developing embryos before they are implanted.

Question 17

Physical contraception

Answer 17

Condom/diaphrahms
IUD
Spermicidal agent
abstaining
surgical methods - vasectomy

Question 18

Oral pill

Answer 18

contains mixture of oestrogen and progesterone that mimics negative feedback effect which prevents release of FSH and lH

Question 19

Mini-pill

Answer 19

contains progestrone only which causes thickening of cervical mucus

Question 20

Morning after pill

Answer 20

Contains stronger doses of oestrogen and progesterone than the contraception pill. Prevents or delays ovulation

Question 21

What type of ART is used to stimulate ovulation

Answer 21

Clomifene

Question 22

Antenatal screening

Answer 22

Used to identify any possible rusk to mother or foetus during pregnancy or identify health issues that will affect the baby

If risk identified further tests can be carried out and prenatal diagnosis given

Question 23

Ultrasound imaging

Answer 23

Dating scan

Anomaly scan

Question 24

Dating scan

Answer 24

carried out weeks 8-14

used to determine stage of pregnancy and due date

used with tests for marker chemicals which vary during pregnancy

Question 25

Anomaly scans

Answer 25

Carried out weeks 18-20 may detect serious physical abnormalities

Question 26

Blood and urine tests

Answer 26

Routine blood and urine tests are carried out throughout pregnancy to monitor the concentrations of marker chemicals. This is why they are used in conjunction with scans, as measuring chemicals at wrong time can lead to false pos can indicate pre-eclampsia and down's syndrome

Question 27

Diagnostic testing

Answer 27

Amniocentesis Chorionic Villus Samping CVS

Question 28

Amniocentisis

Answer 28

Uses small number of amniotic fluid from amniotic sac surrounding foetus to check genetic disorders @ 14-16 weeks sample of amniotic fluid is removed and cultured Approx 2 weeks for results

Question 29

CVS

Answer 29

Tests a sample of cells from mothers placenta for genetic disorder 8 weeks sample of placenta cells removed and cultured immediate karyotyping results

Question 30

what diagnosis has higher miscarriage results

Answer 30

CVS

Question 31

PKU

Answer 31

autosomal recessive inherited metabolic condition sufferers require 2 recessive alleles to be affected heel prick test in newborn babies

Question 32

pedigree analysis chart

Answer 32

how genetic disorders are inherited in a family probability

Question 33

4 types of patterns in inheritance of single gene disorders

Answer 33

autosomal recessive autosomal dominant incomplete dominance sex-linked recessive

Question 34

X and Y

Answer 34

sex chromosomes all others autosomal

Question 35

Autosomal recessive inheritance

Answer 35

Expressed rarely - require 2 recessive alleles (homozygous recessive) may skip generations, affect both genders equally e.g. cystic fibrosis

Question 36

autosomal dominant inheritance

Answer 36

sufferers require one dominant allele so can be homozygous dominant or heterozygous affects both genders equally e.g. Huntington's disease

Question 37

Incomplete dominance

Answer 37

Dominant allele not fully expressed Both incomplete dominance allele are shown with upper case letters in genetic diagrams e.g BW WW BB

Question 38

genotype and phenotype

Answer 38

Phenotype - description Genotype - WW, BB, WB

Question 39

sex-linked recessive inheritance

Answer 39

sex chromosomes mainly responsible for determining gender, carry some genes that code for body functions. men more susceptible

Question 40

Haemophilia

Answer 40

sufferers unable to clot their blood resulting in excessive bleeding, even from small cuts or bruises. Sex-linked - recessive allele on X chromosome