Answer the following question given this paragraph: Q: Many species secrete a hard external skeleton of what? Choices: - sodium bicarbonate - hydrogen carbonate - carbon dioxide - calcium carbonate A:
calcium carbonate

Answer the following question given this paragraph: The right ventricle pumps oxygen-poor blood toward the lungs, where it receives oxygen. Q: The right ventricle pumps what type of blood toward the lungs? Choices: - plasma - oxygenated - oxygen-rich - oxygen-poor A:
oxygen-poor

Answer the following question given this paragraph: Thermal energy is the total energy of moving particles of matter. The transfer of thermal energy is called heat. Therefore, a heating system is a system for the transfer of thermal energy. Regardless of the type of heating system in a home, the basic function is the same: to produce thermal energy and transfer it to air throughout the house. Q: What do you call the transfer of thermal energy? Choices: - formation - humidity - precipitation - heat A:
heat

Answer the following question given this paragraph: Each endocrine hormone affects only certain cells, called target cells. A target cell has proteins on its surface to which a given hormone can bind. Most endocrine hormones are controlled by negative feedback loops. Negative feedback occurs when low levels of a hormone feed back to increase its secretionand vice versa. 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