3 hardy weinberg

Question 1

why are males more likely to be colourblind than females

Answer 1

-females need to have 2 recessive alleles
-males only have 1 allele for eye colour
-females can be heterozygous/ carriers but males cant

Question 2

what are causes of genetic variation

Answer 2

-random fusion of gametes
-crossing over
-independent assortment
-random fertilisation

Question 3

in genetic crosses, the observed phenotypic ratios obtained in the offspring are not the same as the expected ratios, suggest two reasons why

Answer 3

-random fertilisation of gametes
-sample size is small

-linked genes or epistasis

Question 4

what is meant by the term phenotype

Answer 4

the expressed characteristics which are decided by the genotypes
-characteristic/ appearance due to environment

Question 5

using your knowledge on respiration and muscle contraction, explain why mitochondrial disease often causes muscle weakness

Answer 5

-reduction of ATP production by aerobic respiration
-less force generated because fewer actin and myosin interactions in muscle
-fatigue caused by lactate from anaerobic respiration