Answer:
Explanation:
The central nervous system (CNS) does not have capacity to repair itself but, the PNS or the peripheral nervous system can repair and regenerate itself. The PNS can regenerate its damaged axon only when its cell body or cyton and its neurilemma are intact. The proximal end of the cyton has growth cones. The axon grows from the cones.
Scientists developed the time scale by studying rock layers and fossils world wide.
Radioactive dating helped determine the absolute divisions in the time scale. so mass extinction help because there is more to study
Answer:
Explanation:
Cellular respiration occurs in the cells of all living things, both autotrophs and heterotrophs. All of them burn glucose to form ATP. The reactions of cellular respiration can be grouped into three stages: glycolysis, the Krebs cycle (also called the citric acid cycle), and electron transport.