Plasma membrane (notes)

What are the types of passive transport mechanisms in cells?

Simple diffusion, osmosis, and facilitated diffusion.

What is the role of sodium/potassium pump?

It moves sodium out of the cell and potassium into the cell, against their concentration gradients, using ATP.

What does amphipathic mean in the context of phospholipids?

Amphipathic phospholipids have a hydrophilic head and a hydrophobic tail, allowing them to form bilayers in water.

Describe the structure and function of glycoproteins.

Glycoproteins are proteins bound to carbohydrate chains, found on the extracellular surface of the membrane, acting as cell surface markers for recognition.

What is facilitated diffusion?

Facilitated diffusion is the process where specific molecules cross the cell membrane through protein channels, without the expenditure of energy.

What role do aquaporins play in cells?

Aquaporins are transport proteins that facilitate the rapid movement of water molecules across the cell membrane.

What is the significance of selectively permeable membranes?

Selectively permeable membranes allow certain molecules to enter or exit the cell, maintaining homeostasis and specific internal environments.

Explain the process of osmosis.

Osmosis is the movement of water molecules across a selectively permeable membrane from an area of low solute concentration to high solute concentration.

What happens to plant cells in a hypotonic solution?

Plant cells become turgid due to water entering the cell, which is beneficial for maintaining structure and support.

What is the difference between active transport and passive transport?

Active transport requires energy (ATP) to move substances against their concentration gradient, while passive transport does not require energy and moves substances down their concentration gradient.