The two primary functions of DNA are:

A.
to provide energy for the cell and replicate.
B.
to take in oxygen and remove carbon dioxide from the cell.
C.
to direct the activities of the cell and copy itself for new cells.
D.
to digest proteins and carry out photosynthesis.

a. decomposes use carbon from dead organisms as fuel for cellular respiration, returning carbon dioxide back into the atmosphere.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.