HELP ASAP Many living things add oxygen to the oxygen cycle by performing A dehydration

B. respiration

C. mitosis

D. photosynthesis

Which part of cellular respiration must occur before any of the other steps can occur

Plz ! ive been stuck on this forever

Below are the three main organs that make up the plant body. what is the main function of the structure that is identified as b in the picture above? it anchors the plant.it produces food.it absorbs nutrients.it supports the plan