The difference between osmosis and diffusion is that
a. diffusion is passive transport, whereas osmosis is active transport.
b. only in diffusion do molecules move from areas of high concentrations to areas of low concentration.
c. only diffusion refers to the movement of materials across a semipermeable membrane.
d. osmosis refers specifically to the movement of water, whereas diffusion is the movement of molecules.
e. the process of osmosis varies according to the kinds of particles present.
The Correct Answer and Explanation is :
The correct answer is d. osmosis refers specifically to the movement of water, whereas diffusion is the movement of molecules.
Explanation:
Osmosis and diffusion are both passive transport processes that move substances across cell membranes without the use of energy. However, they differ in the types of substances they transport and the mechanisms involved.
Diffusion:
Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration, driven by the concentration gradient. This process continues until equilibrium is reached, meaning the concentration of molecules is uniform throughout the system. Diffusion can occur with any type of molecule, including gases, liquids, and solutes in solutions. For example, oxygen diffuses from the lungs into the bloodstream, and carbon dioxide diffuses from the blood into the lungs to be exhaled. (Wikipedia)
Osmosis:
Osmosis is a specific type of diffusion that involves the movement of water molecules across a selectively permeable membrane. Water moves from an area of higher water potential (lower solute concentration) to an area of lower water potential (higher solute concentration) until equilibrium is achieved. This process is crucial for maintaining proper cell function, as it regulates the internal environment of cells. For instance, plant roots absorb water from the soil through osmosis, and red blood cells maintain their shape and function through osmotic balance. (Wikipedia)
Key Differences:
- Substance Transported: Diffusion involves the movement of various molecules, whereas osmosis specifically involves the movement of water molecules.
- Membrane Permeability: Osmosis requires a selectively permeable membrane that allows water to pass through but may restrict other molecules. Diffusion can occur through any permeable medium, not necessarily a membrane.
- Direction of Movement: In osmosis, water moves toward the area with higher solute concentration to balance solute levels. In diffusion, molecules move from areas of higher concentration to areas of lower concentration to achieve equilibrium.
Understanding these distinctions is essential in fields like biology and chemistry, where the movement of substances across membranes is fundamental to processes such as nutrient absorption, waste removal, and cellular homeostasis.