More than 90% of all mammal species are a) monotremes. b) marsupials. c) placentai mammals. d) domestic animals.

Which macromolecule catalyzes chemical reactions this be considered enzyme chemical reactions thus he considering enzymes

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 cell structures is significantly different between gram- positive and gram-negative bacteria?