Study the image about geologic time. A geochronological scale measured in Millions of Years Ago or M Y A. Cenozoic era: Paleogene period, 66 to 23 M Y A, diatrima, many types of mammals, smilodon. Neogene period, 23 to 2.6 M Y A, smilodon, mammoth. Quaternary period, 2.6 to today, human, mammoth.

During which period did humans first appear on Earth?

Quaternary
Neogene
Paleogene
Cenozoic

Quaternary

Explanation:

The Quaternary period which began around 2.6 million years ago or 2,588,00 years ago is known as the Age of humans.

During this period, the tectonic planets are in a place they are today but the climate was cold and ice glaciers started retreating.

During this period, the evolution of mammals reached on peak and the hominid lines began to evolve as the fossils of the first human belonged to this period. Homo erectus for the first time appeared at the beginning of this period and then evolved later into modern humans after they travelled to Europe and Asia.

Thus, Quaternary is the correct answer.

cellular respiration oxidizes food into energy in the form of atps.

glycolysis (6 c hexose) > 2x atps are used > 6c hexose biphosphate > 2 x 3c triphosphate >

2 x 3c pyruvate (2x nadh produced from nad) and (4x atp produced)

pyruvate actively pumped mitochondrial matrix.