Certain fossils, called index fossils, help geologists match rock layers. To be useful as an index fossil, a fossil must be widely distributed and represent a type of organism that existed for a brief time period. Index fossils are useful because they tell the relative ages of the rock layers in which they occur.
It is the fraction of all chromosomes in the population that carry that allele.
It is a. all genetic material comes from one parent
Answer:
Explanation:
As water temperature increases, the amount of O2 dissolved in water decreases.
The graph looks something like this (though not exactly. It just has the same sort of shape.)
