AP BIOLOGY

Detailed explanation-1: -Active transport involves the expenditure of energy in the form of ATP as the movement of molecules is against the concentration gradient (from low to high concentration) and with the help of special proteins called carrier proteins.

Detailed explanation-2: -Active transport involves molecules moving against a gradient or other form of resistance, such as from an area of lower to higher charge. Active transport is used by cells to accumulate needed molecules such as glucose and amino acids.

Detailed explanation-3: -There are three main active transport methods-ion pumps, exocytosis and endocytosis.

Detailed explanation-4: -Yes, active transport can only be achieved with the help of ATP or Adenosine Triphosphate. Active transport refers to the movement of molecules from an area of lower concentration to an area of higher concentration. This movement against the concentration gradient cannot be achieved without some type of energy.

Detailed explanation-5: -Examples of Active Transport in Animals and Humans Sodium-potassium pump (exchange of sodium and potassium ions across cell walls) Amino acids moving along the human intestinal tract. Calcium ions moving from cardiac muscle cells. Glucose moving in or out of a cell.