Final answer:
Passive transport and active transport are both methods by which molecules move across cell membranes, but they differ in terms of energy requirement and direction of movement. Passive transport occurs without the use of energy and moves molecules from higher to lower concentration, while active transport requires energy and moves molecules from lower to higher concentration.
Step-by-step explanation:
Passive Transport:
Passive transport is the movement of molecules across a cell membrane without the use of energy. It occurs down a concentration gradient, meaning that molecules move from an area of higher concentration to an area of lower concentration. Examples of passive transport include diffusion, osmosis, and facilitated diffusion.
Active Transport:
Active transport, on the other hand, requires the use of energy to move molecules across a cell membrane. It happens against a concentration gradient, meaning that molecules move from an area of lower concentration to an area of higher concentration. Examples of active transport include sodium-potassium pumps and endocytosis.
Similarities:
Both passive and active transport are methods by which molecules move across cell membranes. They both play crucial roles in maintaining homeostasis within the cell. Additionally, both transport mechanisms involve the movement of substances through the phospholipid bilayer of the cell membrane.
Differences:
The main difference between passive and active transport lies in the use of energy. Passive transport does not require energy, while active transport does. Additionally, passive transport moves molecules from higher to lower concentration, while active transport moves molecules from lower to higher concentration. Another difference is that passive transport can occur through simple diffusion, whereas active transport typically involves the use of membrane proteins.
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