[Q] What continues to grow throughout their lives?
Options:
- (A) Chemical energy
- (B) bacteria
- (C) animals
- (D) Humans
- (E) Orange Trees
- (F) Cats
- (G) an organism's body
- (H) Dogs
[A] Here's my solution: Most plants continue to grow throughout their lives. All orange trees are plants. Orange trees continue to grow throughout their lives. The answer is (E).

[Q] One example of an annelid has how many hearts?
Options:
- (A) three
- (B) Five
- (C) white
- (D) warm
- (E) four
- (F) strong
- (G) long
- (H) small
[A] Here's my solution: Annelids are worms such as the familiar earthworm. An earthworm has five hearts. An animal that has five hearts is an annelid. The answer is (B).

[Q] What kind of animal doesn't have a respiratory or excretory system?
Options:
- (A) a fish
- (B) bears
- (C) ant
- (D) whale
- (E) humans
- (F) starfish
- (G) mammals
- (H) llama
[A] Here's my solution: Echinoderms lack respiratory and excretory systems. Starfish and sea urchins are also echinoderms. Starfish lack respiratory and excretory systems. The answer is (F).

[Q] Earthworms have the amazing capacity to regrow segments that:
Options:
- (A) reproduce
- (B) tadpoles
- (C) Loose
- (D) form sand
- (E) are still attached
- (F) allow growth
- (G) break off
- (H) fungal
[A]
Here's my solution: Annelids have the amazing capacity to regrow segments that break off. Earthworms Earthworms are in the phylum Annelids. Earthworms have the amazing capacity to regrow segments that break off. The answer is (G).