The Dynamics of Passive Transport in Cells

The video discusses passive transport, a process where particles move through the cell membrane from high to low concentration without energy. It covers three types: diffusion, osmosis, and facilitated diffusion. Diffusion involves particles moving naturally to achieve equilibrium, exemplified by air freshener spreading in a room. Osmosis is the diffusion of water through a membrane, balancing water and solute concentrations. Facilitated diffusion uses protein channels for larger particles to move along the concentration gradient. All these processes occur naturally without energy expenditure.

What is passive transport?

• Movement of particles against the concentration gradient

• Movement of particles from low to high concentration

• Movement of particles using energy

• Movement of particles from high to low concentration without energy

Which of the following is NOT a type of passive transport?

• Active transport

• Osmosis

• Diffusion

• Facilitated diffusion

What happens to solute particles during diffusion?

• They stay in one place

• They require energy to move

• They move from high to low concentration

• They move from low to high concentration

Which example illustrates diffusion without a semipermeable membrane?

• Salt dissolving in water

• Air freshener spreading in a room

• Glucose entering a cell through protein channels

• Water moving through a cell membrane

What is osmosis specifically concerned with?

• Movement of air molecules

• Movement of protein molecules

• Movement of solute particles

• Movement of water molecules

In osmosis, what can pass through the membrane freely?

• Water molecules

• Large solute particles

• All particles

• None of the particles

What role do protein channels play in facilitated diffusion?

• They prevent molecules from entering the cell

• They allow specific molecules to pass through the membrane

• They act as barriers to diffusion

• They provide energy for transport

Facilitated diffusion is necessary for which type of particles?

• Small particles that can pass through the phospholipid layer

• Large particles that cannot pass through the phospholipid layer

• Any particles that require energy

• Particles that move against the concentration gradient

What is a common feature of all types of passive transport?

• They require energy

• They move particles from low to high concentration

• They occur naturally without energy

• They involve active transport mechanisms

Which of the following statements is true about passive transport?

• It includes diffusion, osmosis, and facilitated diffusion

• It is a type of active transport

• It requires cellular energy

• It moves particles against the concentration gradient