Explain how family resemblance are inherited using your knowledge of genetics?

Question

use an example and provide a proof

Answer 1

You inherit features from your parents, and they from their parents and these are found on chromosomes. Each trait or feature has different versions of a gene (allele), which are found on two chromosomes of the same pair (technically more complex, but lets stay simple here). Each parent will supply you with 1 complete set (23) chromosomes at fertilisation (ie in sperm and eggs) so you get 46 chromosomes.

While the sperm and eggs were developing, they divided (using meiosis which halves the number of chromosomes from 46 to 23). BUT which chromosome version they have "given" you is up to chance ie they could give say 20 chromosomes that their father gave them and only 3 of what their mother gave them. This mixing up of chromosomes at meiosis is called independent assortment. THis ensures you will get a random (and hopefully superior) combination of their chromosomes (this tries to increase variability in individuals).

However because you and any brothers or sisters only have this limited (46) number of chromosomes (BUTthere are technically a lot of various combinations you can get differences between siblings) there is a greater chance of simarlity in features and traits. Compared to another person, you may share certain characteristics (ie. blue eyes, freckles) but they will have a particular combination of chromosomes that will make them genetically different and hence look different.

Identical twins look the same because they have the same combination of chromosomes (coming from the SAME sperm and egg and then split), but fraternal twins are genetically no more similar than any other brother or sister (different egg and sperm).

I hope this helps in some way.....

Answer 2

Looking at your family members, in the wrong tree...cats...