Why is it important that hydrogen bonds are weaker than ionic bonds in DNA?
Give 2 reasons/examples.

Weak bonds may be easily broken but they are very important because they help to determine and stabilize the shapes of biological molecules.

Explanation:

For example, they are important in stabilizing the secondary structure (alpha helix and beta-pleated sheet) of proteins. Hydrogen bonds keep complementary strands of DNA together.

a and c are the answeres

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.