How should you test a hypothesis? a. by writing a mathematical equation b. by making a single observation c. by performing a controlled experiment d. by answering a series of questions

Which of the following statements best describes the relationship between the environment and human health? a. the environment is the only factor that affects human health. b. many aspects of the environment can have an impact on human health. c. human health is impacted by changes in climate. d. the environment has no impact on human health. select the best answer from the choices provided

Because of its structure the cell membrane is known as a phospholipid ? a.bilayer b.molecule c.fluid d.barrier

The pharynx is the structure in the body that serves as a pathway of both air and food. how does the body make sure that food does not get into the lungs? the salivary glands secrete enzymes that pull food out of the air pathway. the small intestine pushes the air out of the digestive system. the pancreas breaks down food in the air pathway. the epiglottis closes the air pathway so that food will not enter it.