This is a substance, like an enzyme, which speeds up chemical reactions, but does not react itself.

Ais a landform that is formed at the mouth of a river from the deposition of sediment carried by the river as the water flows.

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

Which of the following is required of a new drug?me