Biological Processes: Diffusion, Osmosis, and Enzyme Activity

Flashcards covering key concepts related to diffusion, osmosis, and enzyme activity for exam preparation.

What is diffusion?

The net movement of particles from a region of higher concentration to a region of lower concentration down the concentration gradient until equilibrium is reached.

What is a concentration gradient?

The difference in concentration between two regions.

In which state of matter does diffusion occur fastest?

In gases.

What effect does temperature have on diffusion?

Increased temperature leads to increased rate of diffusion.

What is osmosis?

The net movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane.

Define hypertonic solution.

A solution which has a lower water potential than the cell.

What happens to an animal cell in a hypotonic solution?

It swells and may eventually burst due to the influx of water.

What is turgor pressure?

The pressure exerted by the fluid inside the central vacuole against the cell wall in plant cells.

Describe active transport.

The movement of particles from a region of lower concentration to a region of higher concentration using energy from respiration.

What is the role of enzymes?

Enzymes act as biological catalysts that speed up chemical reactions without being changed in the process.

What happens to enzyme activity at optimum temperature?

Enzyme activity is at its highest, with maximum formation of enzyme-substrate complexes.

What are the effects of pH on enzyme activity?

Extreme changes in pH can denature enzymes, altering their active site and reducing catalytic activity.

What occurs when substrate concentration is increased?

The rate of reaction increases until all active sites are occupied, after which the rate remains constant.