AP Biology Unit 2 Review

Front

What are channel proteins and their role in facilitated diffusion?

Back

Channel proteins are integral membrane proteins that form tunnels through which specific molecules can passively diffuse across the cell membrane during facilitated diffusion.

Front

Define osmosis in the context of cellular membranes.

Back

Osmosis is the passive diffusion of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Front

What is active transport and how does it differ from passive transport?

Back

Active transport is the movement of molecules across a cell membrane against their concentration gradient, requiring energy in the form of ATP, unlike passive transport which does not require energy.

Front

Describe the function of vacuoles in a cell.

Back

Vacuoles are membrane-bound sacs within a cell that store water, nutrients, and waste products, helping to maintain cellular homeostasis.

Front

What does the term 'fluid mosaic model' refer to in cell biology?

Back

The fluid mosaic model describes the structure of the cell membrane as a dynamic and flexible arrangement of various proteins and lipids that move laterally within the layer.

Front

Explain the significance of selective permeability in cell membranes.

Back

Selective permeability allows the cell membrane to regulate the entry and exit of substances, maintaining homeostasis and allowing the cell to control its internal environment.

Front

What is the role of ATP in cellular processes?

Back

ATP (adenosine triphosphate) serves as the primary energy currency of the cell, providing energy for various cellular processes, including active transport and metabolic reactions.

Front

How do transport proteins facilitate the movement of substances across the cell membrane?

Back

Transport proteins assist in the movement of substances across the cell membrane by providing a pathway for specific molecules to pass through, either passively or actively.

Front

What is the difference between diffusion and facilitated diffusion?

Back

Diffusion is the passive movement of molecules from an area of higher concentration to an area of lower concentration, while facilitated diffusion involves the use of transport proteins to help specific molecules cross the membrane.

Front

Describe the process of endocytosis and its importance to cells.

Back

Endocytosis is the process by which cells engulf external substances, allowing them to enter the cell in vesicles, which is important for nutrient uptake and cellular signaling.