Question

2 Genetics -Match the terms with the most suitable description.
(Points : 16)

Potential Matches:

1 : recessive

2 : sex-linked

3 : pleiotropy

4 : carrier

5 : dominant

6 : phenotype

7 : polygenic

8 : genotype

Answer

: An allele that can be expressed byan individual that is heterozygous.

: The genetic make-up of anindividual.

: The control of more than onephenotypic character by a single gene.

: The visible physical expression ofan individual's genetic make-up.

: An allele that can only beexpressed when an individual is homozygous.

: A trait controlled by more thanjust a single pair of alleles.

: A trait controlled by a genelocated on either the X or Y chromosomes.

: An individual carrying only oneallele of a recessively inherited disorder.

3. Evolution- Match the terms with the most suitable description.
(Points : 16)

Potential Matches:

1 : hybrid sterility

2 : habitat isolation

3 : hybrid inviability

4 : geographic isolation

5 : mechanical isolation

6 : gamete mortality

7 : temporal isolation

8 : behavioral isolation

Answer

: Because of a single mutation in adevelopmental gene, two closely related species of wasps have aslightly different anatomy of their sex organs making interbreedingimpossible.

: Two species of snakes aremorphologically very similar but breed during differentseasons.

: Two similar species of treehopperslive and feed on two separate species of trees.

: Males of two species of birds usedifferent mating dances to attract their mates.

: Due to a geographic barrier, asmall portion of a population remains isolated and its gene pooldiverges from that of the original population.

: Sperm from a male of one speciesdies in the reproductive tract of the female of a different speciesbefore fertilization can occur

: Mules are a cross between a donkeyand a horse; they are viable, healthy animals, but they cannotreproduce.

: A cross between two species ofsalamanders yields offspring, but they do not survive long enoughto reproduce