Active transport requires energy when moving molecules against a concentration agent. It requires for specific membrane transport proteins. Only a certain type of protein can move a certain type of substance.
The three main types of Active Transport are:
1) Sodium-Potassium Pump
2) Endocytosis
<span>3) Exocytosis </span>
Answer:
WBC.
Explanation:
WBC have cells, hence the name White Blood CELLS. They also contain a nucleus.