Q: Which chemical element is the basis of all life on earth? Choices: - oxygen - nitrogen - hydrogen - carbon A:
carbon

(Question)
Q: Stars are born in clouds, and they form and grow dense due to what force? Choices: - kinetic energy - Big Bang theory - coreolis effect - gravity A:
(Answer)
gravity

Ques: Q: Oxygenated air, taken in during inhalation, diffuses across the surface of the lungs into the what? Choices: - liver - brain - proteins - bloodstream A:
Ans: bloodstream

(Q).
Q: Hormones often regulate what through antagonistic functions? Choices: - hypothesis - consciousness - breathing - homeostasis A:
(A).
homeostasis

Ques:Q: Which vitamin is made in the skin when it is exposed to sunlight? Choices: - Vitamin C - Vitamin B1 - Riboflavin - vitamin d A:

Ans:vitamin d

Q: What are the largest phylum in the animal kingdom? Choices: - crustaceans - cephalopods - mammals - arthropods A:
arthropods