Question

which element is present in all amino acids, but not necessarily in fats or carbohydrates?
oxygen
hydrogen
nitrogen
question 8
3 pts
which statement best describes the role of dna in the body?
it provides long - term energy storage.
it contains genetic information.
it speeds up chemical reactions.
question 9
3 pts
which statement best explains how enzymes speed up chemical reactions?
enzymes gain heat from chemical reactions.
enzymes lower the activation energy of a reaction.
enzymes change shape during chemical reactions.

Explanation:

• For the first question, amino - acids have an amino group (-NH₂) which contains nitrogen. Fats and carbohydrates are composed mainly of carbon, hydrogen, and oxygen and do not necessarily contain nitrogen.
• For the second question, DNA is the molecule that contains the genetic information for the development and functioning of living organisms. It is not involved in long - term energy storage (that's fats) or speeding up chemical reactions (that's enzymes).
• For the third question, enzymes are biological catalysts that speed up chemical reactions by lowering the activation energy required for the reaction to occur.

Answer:

• First question: nitrogen
• Second question: It contains genetic information.
• Third question: Enzymes lower the activation energy of a reaction.