3.4.5 & 3.4.6

Question 1

cystic fibrosis

Answer 1

autosomal recessive disease

a mutation in the CFTR gene–> cause secretions, such as mucus, sweat, digestive juices, which usually thin to become thick

causes difficulty in digesting food

Question 2

Huntington’s disease

Answer 2

caused by a dominant allele that has developed through mutation of the HTT gene on chromosome 4

symptoms=loss of muscle coordination, cognitive decline, psychiatric problems

the occurrence of only 1 copy of the mutated allele is enough to cause the disease since its dominant

Question 3

red-green color blindness

Answer 3

recessive allele for red-green color blindness codes for a non-functional copy of 1 type of photoreceptor protein in the eye’s retina

Question 4

hemophilia

Answer 4

disease in which a protein is needed for blood clotting (factor VIII)

without this factor=cause bleed excessively=might die

gene for clotting factor VIII is on the X chromosome

allele that cause hemophilia is recessive