According to cell theory, which are made of cells? check all that apply.

kitten
bacteria
cactus
mushroom
rock

Kitten, bacteria, cactus and mushroom.

Explanation:

According to the cell theory, all living things are made up of cells and all the new cells are formed from pre-existing cells.

The cell is the smallest structural and functional unit of life and hence, all that is living will be made up of cells. 

From the given list kitten, bacteria, cactus, and mushroom are all living beings and thus are made up of cell however the rock is a nonliving thing and thus is not made of cells.

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.