Cell Membranes and Transport _ S4

Front

What is passive transport?

Back

Passive transport is the movement of molecules across a cell membrane without the use of energy, typically moving from an area of high concentration to an area of low concentration.

Front

Which process is an example of passive transport?

Back

Osmosis is an example of passive transport, specifically the movement of water across a semipermeable membrane.

Front

What are the two parts of a phospholipid?

Back

The two parts of a phospholipid are the hydrophilic head and the hydrophobic tail.

Front

What is the function of integral proteins in the cell membrane?

Back

Integral proteins span the membrane and are involved in transporting substances across the membrane.

Front

What is the sodium-potassium pump?

Back

The sodium-potassium pump is a type of active transport protein that moves sodium ions out of the cell and potassium ions into the cell, using energy.

Front

What does the fluid mosaic model describe?

Back

The fluid mosaic model describes the structure of cell membranes as a mosaic of various proteins that float in or on the fluid lipid bilayer.

Front

What is osmosis?

Back

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

Front

What is the difference between active and passive transport?

Back

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

Front

What is endocytosis?

Back

Endocytosis is the process by which cells take in substances by engulfing them in a membrane.

Front

What is exocytosis?

Back

Exocytosis is the process by which cells expel materials in vesicles that fuse with the plasma membrane.