Question

Q10: Homologous chromosomes typically have… BOLD all that apply

            i. the same genes.

            ii. the same numberof genes.

            iii. the same exact combinationof genes (i.e. the exact same alleles)

            iv. roughly the same size.

Q11: Sister chromatids typically have… BOLD all that apply

            i. the same genes.

            ii. the same numberof genes.

            iii. the same exact combinationof genes (i.e. the same alleles)

            iv. roughly the same size.

Q12:Is it possible for homologous chromosomes to have different alleles?  Yes    or    No

Q14: These two chromosomes are the same size, but if each original pair of socks had been worn differently, these two socks would looks similar but different.  Would you assume that each chromosome has the same general organization? In other words to they contain the same types of genes?

Yes    or   No

Q15:  If you answered “Yes” to the previous question, is it possible that this typeof trait (brown, blue, etc.)  is exactly the same on each chromosome?  Explain your answer.     If you answered “No” to the previous question, explain your reasoning.  

Q16: Is it possible for homologous chromosomes to have any of the same alleles on them?  Explain your answer.

Answer 1

Q10. Homologous chromosomes typically have

i. the same genes.

ii. the same numberof genes.

iv. roughly the same size.

But not the exact same alleles because they come from different parents and thus the alleles must have some differences.

Q11. Sister chromatids typically have

i. the same genes.

ii. the same numberof genes.

iii. the same exact combinationof genes (i.e. the same alleles)

iv. roughly the same size.

All of these are true because sister chromatids are from the same chromosome and are exact copies of each other.

Q12. Yes, it is possible for homologous chromosomes to have different alleles because they come from different parents and thus the alleles must have some differences.

Q14. Yes, they would contain the same types of genes since the two chromosomes are the same size and coding for the same trait. They would be the same type of genes but not exactly the same though.

Q15. No, it is not possible that this type of trait (brown, blue, etc.)  is exactly the same on each chromosome. Inside these homologous chromosomes there are genes which contain alleles for the trait.These alleles mostly follow a dominant/recessive relation in which one of the traits would be dominant (here brown is dominant) while the other(blue) would be recessive. So, if you have one allele for brown eyes and one allele for blue eyes (Bb), your eyes will be brown. (This is also the case if you have two alleles for brown eyes, BB.) However, if both alleles are for the recessive trait (in this case, blue eyes, bb) you will inherit blue eyes.

Q16. No, it is not possible for homologous chromosomes to have any of the same alleles on them because each homologous pair is from different individuals (the mother (called a maternal chromosome) and the father (paternal chromsosome)) and thus even if they carry the same genes in the same order, the alleles for each trait may not be the same.