Ante-and postnatal screening

Question 1

Antenatal or prenatal screening involves testing

Answer 1

for diseases of condition in a fetus or embryo before its born

Question 2

Antenatal screening identifies

Answer 2

the risk of a disorder so that further test and a prenatal diagnosis can be offered

Question 3

antenatal procedures include

Answer 3

ultrasound scanning
amniocentesis
chorionic villus sampling (cvs)
rhesus antibody testing

Question 4

A ultrasound scanner is used to produce

Answer 4

an ultrasound image on computer screen

Question 5

ultrasounds can give information such as

Answer 5

due date

how far along you are

Question 6

ultrasound imaging is also used to produce an anomaly scan which is used

Answer 6

which is used to detect the presence of serious physical problems in the fetus.

Question 7

biochemical test are carried out

Answer 7

to detect maker chemicals that are produced during a normal physiological changes that take place during a pregnancy

Question 8

diagnostic test such as amniocentesis

Answer 8

CVS(chorionic villus sampling) can confirm if baby has

down syndrome as well as any other conditions

Question 9

CELLS from amminoestisis and (CVS) chorionic villus sampling can be cultured to produce a

Answer 9

karyotype

Question 10

karyotype

Answer 10

is a image of an individual’s chromosomes, arranged in homologous pairs.

Question 11

karyotype is used to

Answer 11

identify anomalies in the number or structure of chromosomes

Question 12

Diagnostic test, like amniocentesis and CVS, are invasive and carry a small risk of

Answer 12

inducing miscarriage

Question 13

CVS can be carried

Answer 13

out earlier than amniocentesis, but has a higher risk of inducing miscarriage

Question 14

Rhesus antibody testing is carried out

Answer 14

early in a pregnancy to determine the rhesus status of the mother to ensure that she shows no immune response to her fetus

Question 15

In the event of a second pregnancy, complications can arise if mother is rhesus

Answer 15

negative and the fetus is rhesus positive

Question 16

Anti-rhesus antibodies are given to rhesus

Answer 16

negative mothers after the birth of the baby

Question 17

postnatal screening involves

Answer 17

health checks that are carried out after the birth of the baby.

Question 18

postnatal diagnostic testing is used to detect metabolic disorders

Answer 18

such as phenylketonuria(PKU)

Question 19

PKU is an inborn error of

Answer 19

metabolism caused by an autosomal recessive genetic disorder

Question 20

individuals with PKU cannot metabolise excess

Answer 20

phenylalanine

Question 21

if PKU is not detected soon after birth the baby’s

Answer 21

mental development can be affected

Question 22

individuals with PKU are placed on a restricted diet that lacks the

Answer 22

amino acid phenylalanine

Question 23

pedigree charts(family trees)compiled and used to analyse patterns of inheritance in

Answer 23

genetic screening and counselling

Question 24

pedigree charts are constructed to provide information and advice in situations where there is the is the possibility of

Answer 24

passing on a genetic disorder to potential offspring.

Question 25

pedigree charts can be used to analyse patterns of inheritance involving

Answer 25

autosomal recessive, autosomal dominant, incomplete dominace and sexlinked ressesive single gene disorders

Question 26

homozygous individuals have two

Answer 26

copies of the same allele

Question 27

heterozygous individuals have two

Answer 27

copies of different alleles

Question 28

An autosomal recessive disorders such as cystic fibrosis

Answer 28

it affects males and females equally

expressed relatively rarely in the offspring.

Question 29

An autosomal dominant such as huntington’s disease

Answer 29

shows in every generation

affects males and females equally

Question 30

autosomal incomplete dominance

Answer 30

the fully expressed form of the condition is rare
the partly expressed from is more common
males and females are affected equally

Question 31

sex-linked recessive disorders

Answer 31

• males are affected more than females
• male offspring receive the condition from their mother
• fathers cannot pass the condition on to their sons
• female offspring can only be affected if the father has the condition and the mother is at least a carrier