Cell Membrane Dynamics and Transport Mechanisms

The video explains how cell membranes control material passage, highlighting passive and active transport. It covers diffusion, osmosis, and factors affecting them, such as temperature and particle size. The video also discusses solution types—hypertonic, hypotonic, and isotonic—and their effects on cells, using practical examples like Kool-Aid and red blood cells. Finally, it emphasizes the movement of water from hypotonic to hypertonic solutions.

What is the primary function of the cell membrane?

• To provide energy to the cell

• To store genetic information

• To control the passage of materials in and out of the cell

• To produce proteins

Which type of transport requires energy input?

• Passive transport

• Osmosis

• Active transport

• Diffusion

What is diffusion?

• Movement of solute across a membrane

• Movement of molecules from low to high concentration

• Movement of molecules from high to low concentration

• Movement of water across a membrane

Which factor does NOT affect the rate of diffusion?

• Temperature

• Color of particles

• Concentration gradient

• Size of particles

What is osmosis specifically concerned with?

• Movement of water

• Movement of proteins

• Movement of solute

• Movement of lipids

In a solution, what is the role of the solvent?

• To provide energy

• To be dissolved by the solute

• To act as a barrier

• To dissolve the solute

What does a hypertonic solution have?

• Equal solute and water concentration

• High water concentration

• Low solute concentration

• High solute concentration

In which direction does water move during osmosis?

• From hypertonic to hypotonic

• From hypotonic to hypertonic

• From isotonic to hypertonic

• From isotonic to hypotonic

What happens to a red blood cell in a hypotonic solution?

• It maintains its shape

• It shrivels

• It swells and may burst

• It becomes rigid

What is the effect of an isotonic solution on a cell?

• The cell bursts

• The cell swells

• The cell shrivels

• The cell maintains its normal shape