Q: If gills are used for breathing water by crustaceans, then crustaceans breathe what through their gills? Answer choices: - matter - water - saliva - gametes - semen - liquid - oxygen - air
A: water

Q: If some invertebrates have shells, then some invertebrates may have which feature? Answer choices: - invertebrate - fat - gills - exception - three - mollusk - complex - shell
A: shell

Q: If hummingbirds increase plants genetic diversity, then what animal increases plants genetic diversity? Answer choices: - Reproduction - Plant reproduction - flowers - Hummingbirds - fish - whales - sharks - animals
A: Hummingbirds

Q: If animals in the frog family are the first true tetrapods, then the first tetrapods were? Answer choices: - major threat to health - remains of prehistoric life - in the frog family - running and lifting - competing for resources - warm-blooded - objects that have mass - graptolites
A: in the frog family