Easy. Answer is oxygen because it says which one was missing before any life was on earth. And in order to have life on earth you need oxygen!
:)
There is no process pictured.....
Carbohydrates provide structural support, in the form of cellulose in cell walls, for plants in addition to providing energy for the organism
Proteins are essential for muscle tissue's growth and development as well as, in the form of hormones and hormonal regulation, maintaining an organism's homeostasis.
Lipids make up the bilayer of cell membranes, and also aid hormonal signaling.
Nucleic acids store genetic information, and allow for ribosomal protein synthesis.
Answer:
Explanation:Which characteristic of pea plants were important in their selection as ... Which statement below best describes the difference between mitosis and ... mitosis is the portion of the cell cycle that divides the nuclear material while cytokinesis divides the ... Animal breeders who discover a unique trait and selectively breed to
