Answer:
drinking water after a long run
Explanation:
When there arises a change or shift in the state or action of any organism because of any external stimulus, the result is said to be the response to external stimulus. The response or reaction to the external stimulus arises when the organism experiences or senses the stimulus.
Drinking water after a long run is an example of the response to external stimulus. Here, the external stimulus is the loss of water in the water because of the action of running. This makes the individual drink water which is a response to the external stimulus.
Answer - Theory
Reasoning - Your best bet and term to describe the evolution by natural selection is theory as to still scientific theory/research is still ongoing and changes can be made in a different direction.
UV rays reacting with the O2 molecules
I might be wrong a little but
Hope the helps :)
Answer:
The embryo develops the heart, nervous system and face.
Explanation:
The nervous system is one of the first things to develop, following is the heart and then their face. Physical traits which also develop are the arms, legs and sexual organs.
The worm feeds via a "pumping" action in which it first uptakes the fluid surrounding it. Then, it expels the fluid while trapping any bacteria within it. The bacteria are then digested for energy and nutrients.