Explain, from a molecular perspective, why full siblings do not look alike.?

Question

Please go into as much detail as possible.

Answer 1

When sperm and egg cells are made, they each carry half the parent's genetic material. But each of the parent's genes has two copies, and which copy, number one or number two, ends up in the egg cell or sperm cell, is random. So individual sperm and egg cells can be very different from their fellow sperm and egg cells.

Of course, this means that no two fertilizations, even though they are between the same two people (parents), result in identical fetuses. So siblings aren't identical, although they can look a lot alike.

Identical twins are the result of a single egg undergoing fertilization by a single sperm and later splitting into two fetuses. Identical twins thus have identical genes.

Answer 2

When both parts go through meiosis to create gametes (sex cells like sperm and eggs) 23 of there 46 chromosomes are randomly selected and go through synapsis where on allele (gene) is placed on another chromosome. For example, blue eyes and blond hair. There are millions of combinations for the gamete and then fertilization is random where on random egg pairs with a random sperm to create even more combinations.

Answer 3

the dominant gene in one sperm or egg may not be dominant in anoth and no two genes are exactly alike. in one child the dominant genes may be red hair and blue eyes, in another child from the same parents the genes may be blonde hair and green eyes.