[Q] What is essential for cellular respiration for all aerobic organisms.
Options:
- (A) electron
- (B) glucose
- (C) Energy
- (D) Energy.
- (E) chemicals
- (F) Plants
- (G) fungi
- (H) bacteria
[A] Here's my solution: Oxygen is essential for cellular respiration for all aerobic organisms. Oxygen, for example, is produced by plants. Plants are essential for cellular respiration for all aerobic organisms. The answer is (F).

[Q] What are a major food source for other organisms, including humans?
Options:
- (A) Earthworms
- (B) Soft-bodied invertebrates
- (C) Fully cooking the oysters
- (D) absorb light energy
- (E) remains of prehistoric life
- (F) members of their own species
- (G) Humans
- (H) Lawns
[A] Here's my solution: Mollusks are a major food source for other organisms, including humans. Mollusks are soft-bodied invertebrates. Soft-bodied invertebrates are a major food source for other organisms, including humans. The answer is (B).

[Q] Which of the following can travel longer than migrants each day?
Options:
- (A) humans
- (B) ducks
- (C) Whales
- (D) insects
- (E) fur seals
- (F) mammals
- (G) vehicles
- (H) alpacas
[A] Here's my solution: Migrants typically travel long distances. Whales travel long distances each day. While migrants would typically do so, whales can travel longer each day. The answer is (C).

[Q] Temperature falls from the equator to
Options:
- (A) South Africa
- (B) Antarctica
- (C) Asia
- (D) our planet
- (E) Summer
- (F) during the day
- (G) South America
- (H) It decreases
[A]
Here's my solution: Temperature falls from the equator to the poles. First, strong winds circling Antarctica isolate the atmosphere near the pole the winter. Temperature falls from the equator to Antarctica. The answer is (B).