Answer:
Reproduction.
Explanation:
At the cellular level indicate that the living organisms are made up of the smallest building blocks called cell. It refer to unicellular organisms i.e organism with one cell.
At the cellular level, membranes; for the whole organism, the skin is Reproduction because a single parent cell divides into two cells (offsprings), two divides into four cells and so on. It is called cell division and cell reproduction because a single cell skin divides to produce many cells.
B. trenches .......................
The original source of all energy in a food web is the sun. the sun provides light energy that producers use in photosynthesis. animals eat the producers and other animals eat those animals. the energy flow goes up the web, but it all originated at the sun
Answer:
The hemoglobin molecule has four binding sites for oxygen molecules: the iron atoms in the four heme groups. Thus, each Hb tetramer can bind four oxygen molecules.
That is true, species can breed within