Why did the skeleton climb the tree

What type of organism is a one-celled organism that functions as a single unit? a. bi-celled b. single-celled c. pre-celled d. multi-celled

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 is it called when part of a cell membrane closes around a molecule to allow the molecule to enter the cell? a. passive transport b.diffusion c. endocytosis d. exocytosisc. endocytosis