True!
A buffer is a solution that helps in resisting the change in the pH when a acid or base is added to it. Cells contain a lot of different organelle inside them. Each organelle performs a different kind of function and thus has a pH different from the cytoplasm, example mitochondria which has a pH lower than that of the cytoplasm. These organelle maintain a pH buffer within them to resist a change in the environment that will hamper the functioning of proteins in it. Cells like the organelle also maintain a pH buffer in their cytoplasm to resist changes in the pH level due to pH changes in the external environment. This is a way in which the cellular homeostasis takes place.
Answer: DNA has three components a phosphate group, a sugar deoxyribose and 4 nitogenous bases.
DNA has two important bonds that make up the DNA which are phosphodiester bond and hydrogen bonds.
Explanation:
The phosphate of the one nucleotide in DNA bonds with the 5 sugar (5' carbon) of the next nucleotide forming the PHOSPHODIESTER BOND which is a strong covalent bond.
The other bond in DNA is the hydrogen bonds which are among the nitrogenous bases.
There are four bases adenine,guanine,cytosine,thyamine
These bases are held together by strong hydrogen bonds.
Adenine and thyamine have two hydrogen bonds between them and cytosine and guanine have three hydrogen bonds between them.
These hydrogen bonds keeps the DNA helix in place.