In photosynthesis, using light energy, plants convert CO2 and H2O into O2 and C6H12O6
CO2= carbon dioxide
H2O= water
O2= oxygen
C6H12O6= glucose
The best answer is D.
Hormones are chemical messengers secreted mostly into blood and also extracellular fluid by specialized tissue of the endocrine system and affect the functioning of other tissues or cells.
Most hormones circulate in blood and come in contact with essentially all cells, but a particular hormone will only affect a limited number of cells, which are termed as target cells to that hormone.
A target cell responds to a particular hormone because it bears receptors for that hormone.
For example the red blood cells have receptors for the hormone called insulin which is produced by the pancreas. The red cells are able to take in glucose when their receptors bind to insulin.
Answer:
oxygen because
Explanation:
because u can survive 3 days with out it and if u did not have oxygen u would suffocate
the skin has cells like that