I believe the answer is 1) Obtain Energy
You can classify them according to the way they get their food because if they eat plants, then they are herbivores. If animals eat herbivores, then they are consumers. Etc.
It would be 2) two atoms exchange electrons and become ions
Because the molecules that are being transported is moving against its concentration. gradient. in other words, its moving from where it's low in concentration to where it's high in concentration.
<span>There are two types of stimulus that travel within our body. The two types are chemical and electrical. Electrical stimulus is the type of stimulus that travels from the motor neuron to the skeletal muscle. Electrical muscle stimulation is the elicitation of muscle contraction using electric impulses.</span>