2. Which of the following statement(s) are true about the atoms of any element?
A. The number of protons in an atom of an element is unique to each element.
B. The number of protons and neutrons in an atom of an element is unique to each element
C. A proton in an atom of one element is identical to a proton in an atom of another element.
D. The number of protons in an atom of an element is the same for all elements

individual oxygen atoms are formed during photosynthesis.-c.

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation: