What is the difference between undifferentiated sperm cells and sperm?

All living organisms are composed of a. only one cell. b. at least 100 cells. c. at least three cells. d. one or more cells.

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.

What does the number 18.9984 represent in the image?