AP Biology Unit 2 Review

Front

What is the principal driving force behind diffusion?

Back

Concentration gradient.

Front

How can an organism maintain membrane fluidity in fluctuating temperatures?

Back

By having a greater proportion of unsaturated phospholipids in membranes.

Front

What characteristic of a phospholipid increases membrane fluidity?

Back

Double bonds in the fatty acid tail.

Front

How do molecular size, temperature, solution density, and distance affect the rate of diffusion?

Back

Larger molecules move slower than lighter molecules. Temperature affects molecular movement. Density is inversely proportional to molecular movement. Greater distance slows diffusion.

Front

Which component of the plasma membrane can be found on its surface or embedded in the membrane?

Back

Protein.

Front

Define diffusion in biological terms.

Back

The movement of molecules from an area of higher concentration to an area of lower concentration.

Front

What role do unsaturated fatty acids play in membrane structure?

Back

They increase membrane fluidity, allowing for better movement of proteins and lipids within the membrane.

Front

Explain the significance of the fluid mosaic model of the plasma membrane.

Back

It describes the plasma membrane as a dynamic and flexible structure with various proteins embedded, allowing for movement and interaction.

Front

What is the effect of temperature on the rate of diffusion?

Back

Increasing temperature generally increases the kinetic energy of molecules, leading to a higher rate of diffusion.

Front

How does molecular size influence diffusion rates?

Back

Larger molecules tend to diffuse more slowly than smaller molecules due to their size.