Answer:
D. all of the above
Explanation:
Australopithecus (first ape-man): Australopithecus is considered as the connecting link between apes and man as they shared the characteristics of both. The fossil records shows that they appeared around 5 million years ago. <em>Australopithecus africanus</em> was about 1.5 meters high and had human as well as ape like features. It was with bipedal locomotion, omnivorous in their diet and had erect posture. It had human like teeth with small canines and large chewing teeth. The brain was more like an ape with the brain capacity of about 500 cc similar to that of an ape. He lived in caves, had projected brow ridges with no chin. Its believed that <em>Australopithecus africanus</em> gave rise to <em>Homo habilis</em> about 2 million years ago.
The earliest species of Homo genus is <em>Homo habilis</em>. They were skill full man also called as handy man or the tool maker. He had erect posture with bipedal locomotion. The teeth were like modern man. He was skilled and made tools with stones. Slowly with evolution the prognathous face changed to orthognathous in cro magnon (<em>Homo sapiens fossilis</em>).
Ribosomes and endoplasmic reticulum
<span>Adenosine triphosphate (ATP) consists of an adenosine molecule bonded to three phophate groups in a row. In a process called cellular respiration, chemical energy in food is converted into chemical energy that the cell can use, and stores it in molecules of ATP. This occurs when a molecule of adenosine diphosphate (ADP) uses the energy released during cellular respiration to bond with a third phosphate group, becoming a molecule of ATP. So the energy from cellular respiration is stored in the bond between the 2nd and 3rd phosphate groups of ATP. When the cell needs energy to do work, ATP loses its 3rd phosphate group, releasing energy stored in the bond that the cell can use to do work. Now its back to being ADP and is ready to store the energy from respiration by bonding with a 3rd phosphate group. ADP and ATP constantly convert back and forth in this manner.</span>
Answer:
The correct anwser is D. Signals inside the spinal cord
Explanation:
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