By manipulating the substrates of the reaction, the enzyme can lower the necessary energy needed to make the reaction occur.
The central nervous system is made up of mainly the brain and the spinal cord while the peripheral nervous system is divided into two types which are sensory and motor neurons. The somatic nervous system is associated with voluntary nerves while the autonomic nervous system is also known as involuntary nervous system. The sympathetic nervous system increases or speeds up a process while the parasympathetic nervous system decreases or slows down a process.
Answer:
Paleontologists didn't have the technology in that time to get a good estimation on the events. Back then, they had to rely on natural sources "markers" that made the estimations. Those estimations weren't accurate. Today's measures are accurate.