For giving you understanding ; we need Free O2 but Oxygen is also available in H20 right why dont we use it !!
As the early atmosphere was reducing as there was no free oxygen but it was later produced by chemoautotrophic bacteria !! Living thing release O2 in atmosphere thus making it oxidising in nature and then life evolves !!
A is the answer
a replication fork
Answer:
Carbohydrates consist of the elements carbon (C), hydrogen (H) and oxygen (O) with a ratio of hydrogen twice that of carbon and oxygen. Carbohydrates include sugars, starches, cellulose and many other compounds found in living organisms. In their basic form, carbohydrates are simple sugars or monosaccharides.
:
Buffers in our blood are able to neutralize changes in the bloods pH.
Answer:
oxygen
Explanation:
we need oxygen don't mind me