More Flashcards
(17 cards)
What is the main role of the cell membrane in maintaining the cell’s structure?
It maintains and preserves the integrity of the cell.
How does the cell membrane control the movement of substances in and out of the cell?
By allowing passive diffusion, facilitated diffusion, active transport, and selective transport.
What is passive diffusion?
The movement of simple substances like water and some ions across the membrane without energy.
What substances typically pass through the membrane via passive diffusion?
Water and some small ions.
What is facilitated diffusion?
Movement of substances like glucose and amino acids across the membrane using carrier proteins, without needing energy.
Why does facilitated diffusion not require energy?
Because it occurs along the concentration gradient.
What is the role of carrier proteins in facilitated diffusion?
They help specific substances pass through the membrane.
What is active transport?
Movement of substances against the concentration gradient, requiring energy (ATP).
Why is energy needed in active transport?
Because substances are moved from low to high concentration.
What is selective transport?
A process where membrane receptors select and allow specific substances to enter the cell
What role do receptors on the cell membrane play in selective transport?
They identify and allow only specific substances to enter the cell.
What is phagocytosis?
The process where the cell engulfs large particles or microorganisms.
What is pinocytosis?
The process where the cell takes in fluid and dissolved substances.
How is pinocytosis different from phagocytosis?
Pinocytosis involves fluids, while phagocytosis involves solids or particles.
How does the cell membrane help regulate interaction between cells?
Through special types of cell junctions.
What are cell junctions?
Structures that connect adjacent cells and help in communication and cohesion.
What is Exocytosis ?
The process by which the cell expels materials in vesicles to the outside.
