Cell Membrane Structure and Function Explained

The video explains the structure of the cell membrane, described as a fluid mosaic. It consists of a lipid bilayer with hydrophilic heads and hydrophobic tails. Proteins and carbohydrates are embedded in the membrane, aiding in the movement of substances. Small molecules pass through spaces in the bilayer, while larger ones use protein channels.

What analogy is used to describe the structure of the cell membrane?

• A brick wall

• A rigid structure

• A fluid mosaic

• A solid barrier

What is the primary composition of the cell membrane?

• Double layer of proteins

• Lipid bilayer

• Carbohydrate chains

• Single layer of lipids

How do phospholipids in the cell membrane move?

• In a rigid, fixed manner

• In a flexible, wave-like motion

• They do not move

• In a circular motion

What characteristic do the phospholipid heads have?

• Non-polar

• Hydrophilic

• Hydrophobic

• Neutral

Where are the hydrophilic heads of the phospholipids oriented?

• Toward the extracellular fluid and cytoplasm

• Toward the cell nucleus

• Away from water

• Toward each other

What is the role of proteins in the cell membrane?

• They form a rigid structure

• They provide energy

• They store genetic information

• They assist in substance movement

What is the function of carbohydrates attached to proteins in the cell membrane?

• Cell recognition and signaling

• Transport of molecules

• Energy storage

• Structural support

How do larger molecules pass through the cell membrane?

• Through small gaps in the lipid bilayer

• By dissolving in the lipid layer

• Through protein tunnels

• By breaking the membrane

What is the main function of the cell membrane?

• To produce proteins

• To provide energy to the cell

• To control the movement of substances in and out of the cell

• To store genetic information