Q: What forms when an atom gains electrons? Choices: - cations - bonds - crystals - anions A:
anions

(Question)
Q: What is another term for chemical messenger molecules? Choices: - pheromones - enzymes - acids - hormones A:
(Answer)
hormones

Ques: Q: Minerals are grouped based on what? Choices: - carbon composition - mineral composition - density - chemical composition A:
Ans: chemical composition

(Q).
Q: What is a rigid layer that surrounds the plasma membrane of a plant cell? Choices: - the nucleic wall - the cell center - mitochondria - the cell wall A:
(A).
the cell wall

Ques:Q: Life on earth is carbon-based. organisms need not only energy but also carbon ________ for building bodies? Choices: - monoxide - ions - crystals - atoms A:

Ans:atoms

Ques:Q: Opportunistic diseases are usually the direct cause of death of people with what disease? Choices: - heart - parkinson - liver - aids A:

Ans:
aids