Inheritance (paper 2)

Question 1

allele =

Answer 1

difference versions of the same gene

Question 2

what is the effect of the alleles present

Answer 2

the alleles present / genotype operate at a molecular level to develop characteristics that can be expressed as a phenotype

Question 3

dominant allele =

Answer 3

only 1 copy needed for it to be expressed

Question 4

Recessive allele

Answer 4

2 copies needed for it to be expressed

Question 5

genotypes

Answer 5

the allele the person has

Question 6

homozygous

Answer 6

2 of the same alleles

Question 7

hetrozygous

Answer 7

2 **different* alleles

Question 8

what are inherited disorders caused by

Answer 8

the inheritance of certain alleles

Question 9

name 2 types of inherited disorders

Answer 9

1. Polydactyly
2. Cystic fibrosis

Question 10

is polydactyly caused by a dominant or recessive allele

Answer 10

Dominant:
- anyone who has allele will suffer disorder
- parents with polydactyly can pass it onto children

Question 11

is cystic fibrosis caused by a dominant or recessive allele

Answer 11

recessive:
- must inherit 2 recessive cystic fibrosis alleles
- parents who have 1 allele will no suffer, but can pass it onto children . Known as carriers

Question 12

what can you do to seen if unborn child has genetic disorder

Answer 12

embryo screening - raises economic, social and ethical issues

Question 13

an ordinary human body cell contains how many pairs of chromosomes

Answer 13

23

Question 14

how many pairs of chromosomes control characteristics and what are they called

Answer 14

22 = autosomes

Question 15

what does that one pair determin

Answer 15

biological sex = heterosomes

Question 16

what is the sex chromosome for females

Answer 16

XX

Question 17

what is the sex chromosome for males

Answer 17

XY

Question 18

what are the advantages of embryo screening

Answer 18

• doctors can determine whether child will have an increased risk of having a particular illness / disease
• prepares parents for possibility of a child developing a disorder
• carriers of genetic disorders could make informed decisions on whether to have children

Question 19

what are the disadvantages of embryo screening

Answer 19

• could result in unborn child being aborted if their genetic makeup is ‘faulty’
• parents may want to choose the genetic makeup of their child
• has potential to be used to determine who can/cannot reproduce
• could stigmatise + upset people to learn they carry a genetic disorder