reproduction and inheritance 2

Question 1

what is the definition of an allele?

Answer 1

a version of a gene

Question 2

what is the definition of a dominant allele?

Answer 2

• an allele that only needs one allele present to be expressed

Question 3

what is the definition of a recessive allele

Answer 3

• an allele that needs two alleles to be expressed

Question 4

when do you use the genetic cross FOIL

Answer 4

when both parents are homozygous

Question 5

when do you use the punnet square

Answer 5

when the parents are heterozygous

Question 6

what is the definition of homozygous

Answer 6

both alleles are the same in an individual

Question 7

what is the definition of heterozygous

Answer 7

alleles are different in an individual

Question 8

what is the definition of genotype

Answer 8

genetic composition of an individual

Question 9

what is the definition of phenotype

Answer 9

physical expression of a gene (characteristics)

Question 10

what is the definition of co-dominance

Answer 10

• when both alleles are expressed as their phenotype
  -no dominant or recessive

Question 11

what is the result for each of Gregor Mendel’s experiments

Answer 11

• there was no in-between value
• they were discontinuous

Question 12

what does cystic fibrosis affect?

Answer 12

• the CFTR protein
• causes mucus to become extremally thick

Question 13

what observations did Charles darwin make on evolution by natural selection

Answer 13

• all living things show variation
• all living things tend to overly reproduce

Question 14

what deductions did charles dawin make on his observations of evolution by natural selection

Answer 14

• there will be a ‘struggle for existence’ because organisms over reproduce and therefore resources will be limited
• some will be better adapted to their environment
• those best adapted will survive and reproduce in greater numbers than the less well adapted