Answer:
541 million years ago with the Cambrian explosion, an extraordinary diversification of marine animals, and ended about 252 million years ago with the end-Permian extinction, the greatest extinction event in Earth history.
source- Britannica
Explanation:
Since you did not give a list of choices,here are some reasons why l<span>iving cells cannot use heat to provide the activation energy for biochemical reactions:
</span>
>Heat can never be used to do work.
>Heat is not readily available to all living cells.
>Heat doesn't provide the activation energy for their reactions.
There are options for this question they are:
a) neutral stimulus; conditioned stimulus
b) conditioned stimulus; neutral stimulus
c) unconditioned stimulus; conditioned stimulus
d) neutral stimulus; unconditioned stimulus
e) unconditioned stimulus; neutral stimulus
The correct answers are - In this example, the buzzer begins as the neutral stimulus and eventually becomes the conditioned stimulus. The buzzer initially is a neutral stimulus because it have no role to play in the blinking response. Eventually though through learned association the buzzer becomes a conditioned stimulus because you now associate it with a puff of air to the eye which in turn causes you to blink.
Answer:
humans can eat fish that has plastic in it and that could poison the person
