Factors that a scientist chooses to keep constant over the course of the experiment are called?

Which blood cell spend most of their time in the lymphatic system?

In a vegetable garden 45 bean plants have been eaten by deer 5 are untouched what is the frequency of bean plants in the garden that have been eaten?

Nephrons, the functional unit of kidneys, are responsible for formation of urine. the sentences describe situations that are the result of problems in the urine formation process. for the nephron shown below, match each situation to the step in the urine formation process where the problem lies.