I need help filling this in for a study packet

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.

With regard to enzymes, key is to lock as a) substrate is to activation energy eliminate b) product is to substrate. c) enzyme is to active site. d) substrate is to active site.

Which of the following statements is accurate about evolution? question 10 options: natural selection only eliminates odd individuals. evolution means that a population never has changes in its genetic frequencies. mutations are always harmful. evolution means that a population undergoes changes in its gene frequencies over time.