Q: Many species secrete a hard external skeleton of what? Choices: - sodium bicarbonate - hydrogen carbonate - carbon dioxide - calcium carbonate A:
calcium carbonate

Q: The right ventricle pumps what type of blood toward the lungs? Choices: - plasma - oxygenated - oxygen-rich - oxygen-poor A:
oxygen-poor

Q: What do you call the transfer of thermal energy? Choices: - formation - humidity - precipitation - heat A:
heat

Q: Each endocrine hormone affects only certain "target" cells, which have molecules of what on the surface that enable binding of a given hormone? Choices: - lipids - rna - gas - protein A:
protein