Biology Chapter on Osmosis and Membranes

Questions and Answers

What is osmosis?

Movement of water against a concentration gradient

Diffusion of water across a membrane (correct)

Movement of solute from high to low concentration

Diffusion of solute across a membrane

What does a selectively permeable membrane do?

Allows certain substances to cross more easily than others.

What is a solute?

Minor component in a solution that dissolves.

What is a solvent?

A substance that can dissolve other substances; water is the universal solvent. Signup and view all the answers

What defines a solution?

A mix of solute and solvent. Signup and view all the answers

What does hydrophilic mean?

Water-loving. Signup and view all the answers

What does hydrophobic mean?

Water-fearing. Signup and view all the answers

How does water move in osmosis?

From the area of lower concentration to the area of higher concentration. Signup and view all the answers

What are polar molecules?

Molecules that cluster around hydrophilic solute molecules. Signup and view all the answers

What is net movement in the context of osmosis?

Water moves down its own concentration gradient. Signup and view all the answers

Study Notes

Osmosis and Membranes

Osmosis refers to the diffusion of water across a selectively permeable membrane, equalizing solute concentrations on both sides.
A selectively permeable membrane permits certain substances to pass through more easily, impacting the movement of water and solutes.

Solutions and Components

Solute is the minor component in a solution that dissolves in a solvent; it plays a crucial role in determining solution concentration.
Solvent is the substance in which solutes dissolve; water is known as the universal solvent due to its ability to dissolve many substances.
A solution is the resulting mixture of solute and solvent, where both components are evenly distributed.

Molecular Properties

Hydrophilic substances are those that are attracted to water; they tend to dissolve easily in aqueous environments.
Hydrophobic substances repel water, often leading to separation from aqueous solutions.

Water Dynamics

Water movement typically flows from areas of low solute concentration (high free water molecules) to areas of high solute concentration (low free water molecules).
Polar molecules interact with water by clustering around hydrophilic solute molecules, enhancing solubility in water.
Net movement of water occurs down its concentration gradient, emphasizing the natural tendency for water to move towards areas of higher solute concentration until equilibrium is reached.

Description

Explore the concepts of osmosis, selectively permeable membranes, and the roles of solute and solvent in solutions. This quiz covers the molecular properties related to water dynamics, including hydrophilic and hydrophobic substances. Test your knowledge on how water interacts with different components in biological systems.