Question

1. Describe two kinds of recombination in eukaryotes.

True of False

2._____ A recessive phenotype can be expressed by some progeny of a monohybrid cross.

3._____ Epistatic genes may result from dominant or recessive alleles.
4._____ At a single locus, a diploid individual may have more than two different alleles.
5. _____ A temperature-sensitive allele is an example of a genotype x environment interaction.
6. _____ All of the genetic material in a eukaryotic cell is found in the nucleus.
7. _____ Sex-limited traits are, by definition, encoded by genes on the sex chromosomes.
8. _____ In some XX-XY species, genes on the X chromosome in females have one-half the
expression level of the same genes in males.
9. _____ Type 1 diabetes shows 53% concordance in monozygotic twins and 11% concordance in dizygotic twins, suggesting that genetic variation has no effect on this trait.
10. _____ A gene can have more than two alleles in a population.
11. _____ Linked genes cannot have recombination frequencies that are higher than 50%.
12. _____ The higher the coefficient of coincidence, the higher the degree of crossover interference.

Answer 1

Answer

1) In eukaryotes two types of recombination occurs. In homologous recombination, it happens between similar molecules (homologs). it usually happens in DNA repairing both in mitosis and meiosis.

In non-hologous recombination, recombination occurs between molecules with no sequence homology. This causes chromosomal translocations leading to cancers.

2) True

3) True

4) True

5) True

6) False

7) False

8) False

9) False. Genetic variation has an effect on this trait.

10) True

11) True

12) False