What is the process in which two gametes unite

The following image is of a diatom. it lives in water and gets food from photosynthesis. it is encased in a hard shell made of something similar to glass or sand . a diatom is a(n) because it has a) multi-celled organism; specialized parts. b) vertebrate; a skeleton. c) insect; an exoskeleton. d) single-called organism; only one cell.

Could someone me with number one you

Which of the following shows the results that you would get if you tested beef using the four tests in the gizmo