<span>Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.</span>
Answer:
i might be wrong but i would go with cell wall
Explanation:
Answer: A variable within a scientific experiment is something that is changed (i.e. it varies). There should be only one manipulated variable within a scientific experiment so that the experimenter can be certain it is this variable which causes a pattern in the resultant data, if any exists at all.
Explanation:
The building blocks of DNA are called nucleotides which is composed of a five carbon- sugar group, phospahate bond and four bases of nitrogen groups. this makes the DNA intact. The hydrogen bonds holds the c<span>omplementary base pairs together at the nitrogen bases. The nitrogen bases are uracil, guanine, thymine and adenine.</span>
