Antenatal and postnatal screening

Question 1

3 aspects of antenatal care

Answer 1

-Ultrasound imaging scans
-Blood and urine (biochemical) tests
-Diagnostic testing

Question 2

What are dating scans

Answer 2

They happen at around 8-14 weeks and determine pregnancy and due date

Question 3

What is an anomaly scan

Answer 3

Happens at around 18-20 weeks and detects serious physical abnormalities in the fetus

Question 4

Why are routine blood and urine tests carried out

Answer 4

To monitor concentrations of marker chemicals

Question 5

What does an atypical marker chemical concentration lead to

Answer 5

Diagnostic testing to determine if the foetus has a medical condition

Question 6

What happens if you measure marker chemicals at the wrong time

Answer 6

Lead to a false positive result. Occurs when the chemical is measured at an inappropriate time and found to be high and significance is attributed to it incorrectly. This could show the foetus to have a condition when it doesnt.

Question 7

What does diagnostic testing produce results for

Answer 7

It can establish whether a person is suffering a specific condition or disorder

Question 8

When is diagnostic testing offered to the mother

Answer 8

If any problems occur from routine screening tests
There is history of genetic disorders in the family
The woman is over 35 years of age

Question 9

What is an amniocentesis

Answer 9

Carried out at about 14-16 weeks
A small volume of amniotic fluid containing foetal cells is withdrawn, and then cultured to produce a karyotype.

Question 10

What is chorionic villus sampling

Answer 10

Carried out from 8 weeks into pregnancy
A sample of placental cells are taken and then cultured and used for karyotyping

Question 11

What is a karyotype

Answer 11

A visual display of a persons complete chromosome complement, arranged in homologous pairs.

Question 12

Adv/Disadv of CVS vs Amniocentesis

Answer 12

CVS can occur at a much earlier stage in the pregnancy but holds a higher risk of miscarriage

Question 13

What is Phenylketonuria

Answer 13

Metabolism error, someone born with increased levels of phenylalanine

Question 14

What does a build up oh phenylalanine cause

Answer 14

An affect on the Mental development of a child

Question 15

Indicators that a trait is autosomal recessive

Answer 15

• M and F effected equally
• Trait expressed rarely
• Trait may skip generations
• All sufferers are homozygous recessive

Question 16

Indicators that a trait is autosomal dominant

Answer 16

• M and F effected equally
• Trait appears in every generation
• Each sufferer has an affected parent
• Wgeb a branch of the family does not express the trait, it will never appear in that branch

Question 17

Indicators thag show autosomal incomplete dominance

Answer 17

• Fully expressed form occurs quite rarely
• Partially expresses occurs much more frequently
• Everything is all caps

Question 18

Indicators for sex linked recessive

Answer 18

Makes more often affected
None of the sons of an affected male show the trait
Trait may skip generations