Answer:
keratin, collagen, and elastin are some
Explanation:
Answer:
Oxygen
Explanation:
A waste product of photosynthesis organisms need for cellular respiration is oxygen. We breathe out carbon dioxide and plants use carbon dioxide during photosynthesis and in return they give us oxygen which is their waste product.
The cells increase without an increase in size
Single felled zygotes divide into smaller and smaller cells
That would be : adenine, thymine, guanine, and cytosine.
