But an egg or sperm only has one. That one is chosen at random, through a process called meiosis. When meiosis messes up, you can end up with to many or too few chromosomes. One extra chromosome in a egg or sperm means three in the fertilized egg and so trisomy.
At sunrise and sunset, the sun is lowest in the sky, so it creates longer shadows. The shadows are the longest at these times than other times.
Certain fish that live or depend on coral will most likely be extinct
genes is the answer
A gene mutation is a permanent alteration in the DNA sequence that makes up a gene, such that the sequence differs from what is found in most people. Mutations range in size; they can affect anywhere from a single DNA building block (base pair) to a large segment of a chromosome that includes multiple genes.
B is the answer.
Hope this helps!
