Cell Membrane Structure and Function

The video explores the fluid mosaic model of cell membranes, emphasizing the balance of fluidity and stability. It details the roles of saturated and unsaturated fatty acids, cholesterol, and their impact on membrane permeability. Vesicle transport mechanisms like endocytosis and exocytosis are explained, along with neural signaling involving ion channels. The video also covers active transport, co-transport, and the function of cell adhesion molecules in forming tissues.

What is the primary structural component of the cell membrane that contributes to its fluidity?

• Phospholipids

• Carbohydrates

• Nucleic acids

• Proteins

How do unsaturated fatty acids affect the cell membrane?

• They increase membrane fluidity.

• They decrease membrane permeability.

• They have no effect on the membrane.

• They make the membrane more rigid.

What role does cholesterol play in the cell membrane at high temperatures?

• It makes the membrane more permeable.

• It prevents the membrane from becoming too permeable.

• It solidifies the membrane.

• It has no effect on the membrane.

What is the process called when a cell takes in extracellular fluid by forming a vesicle?

• Exocytosis

• Endocytosis

• Diffusion

• Osmosis

Which process involves the fusion of vesicles with the cell membrane to expel waste?

• Endocytosis

• Exocytosis

• Facilitated diffusion

• Active transport

What triggers the opening of sodium channels in neurons?

• Light exposure

• Temperature change

• Chemical binding

• Voltage change

What is the function of the sodium-potassium pump in neurons?

• To move sodium ions into the cell and potassium ions out

• To maintain equal ion concentrations inside and outside the cell

• To facilitate passive transport

• To establish an electrochemical gradient

What is the main function of nicotinic acetylcholine receptors?

• To transport potassium ions

• To bind neurotransmitters

• To facilitate glucose transport

• To bind sodium ions

What is co-transport?

• The facilitated diffusion of glucose

• The active transport of two molecules together

• The passive diffusion of ions

• The movement of a single molecule across the membrane

What is the role of cell adhesion molecules (CAMs)?

• To hold adjacent cells together

• To facilitate endocytosis

• To increase membrane fluidity

• To transport ions across the membrane