B2.1 Membranes and Membrane Transport

Open Ended

Why is the structure and function of cell membranes important for living organisms?

Multiple Choice

Which of the following best describes the main function of biological membranes in cells?

• They provide energy for cellular processes.

• They control the movement of substances into and out of the cell.

• They store genetic information.

• They produce proteins for the cell.

Open Ended

What determines whether a substance can pass through a biological membrane?

Open Ended

How do molecules of lipid and protein assemble into biological membranes?

Multiple Choice

Which of the following is NOT a key topic covered under 'Membranes and Membrane Transport' in the IB curriculum?

• Lipid bilayers as barriers

• Simple diffusion across membranes

• Photosynthesis in chloroplasts

• Integral and peripheral proteins in membranes

Open Ended

Explain the significance of the fluid mosaic model in understanding membrane structure and function.

Multiple Select

Select all terms that are directly related to the structure and function of biological membranes.

• Phospholipid Bilayer

• Glycoproteins

• Kinetic Theory

• Protein Pumps

Multiple Choice

Which part of a phospholipid is hydrophilic?

• Phosphate head

• Fatty acid tails

• Glycerol backbone

• Hydrocarbon chain

Open Ended

Outline the structure of phospholipids.

Multiple Choice

What happens when phospholipids are added to water?

• They form a bilayer with hydrophilic heads facing water and hydrophobic tails inside

• They dissolve completely

• They form a single layer with tails facing water

• They do not interact with water

Multiple Choice

Which of the following particles can pass directly through the phospholipid bilayer?

• Hydrophobic (uncharged) particles

• Large polar molecules

• Hydrophilic ions

• Charged particles

Open Ended

Explain how the structure of phospholipids allows them to form barriers in biological membranes.

Open Ended

Explain how the kinetic theory relates to the process of diffusion and osmosis in cells.

Multiple Select

Which of the following are characteristics of diffusion as described in the slides?

• It is a passive process

• It requires energy from the cell

• It moves particles from high to low concentration

• It only occurs in liquids

Multiple Choice

Which of the following statements best describes simple diffusion across membranes?

• Movement of water molecules through a protein channel

• Movement of oxygen and carbon dioxide molecules between phospholipids

• Active transport of ions using ATP

• Endocytosis of large particles

Open Ended

Describe the structural features that allow integral proteins to be permanently attached to the plasma membrane.

Multiple Choice

What is the main difference between integral and peripheral proteins in membranes?

• Integral proteins are only found on the surface, while peripheral proteins penetrate the membrane

• Integral proteins are embedded in the lipid bilayer, while peripheral proteins are attached to the surface

• Peripheral proteins are glycoproteins, while integral proteins are not

• Peripheral proteins use energy to transport molecules, while integral proteins do not

Multiple Choice

Which of the following statements best describes peripheral proteins in the cell membrane?

• They are permanently embedded within the membrane.

• They are temporarily attached to one side of the membrane and are hydrophilic.

• They penetrate the phospholipid bilayer completely.

• They are responsible for transporting ions across the membrane.

Open Ended

Explain the difference in location and function between peripheral and integral proteins in the phospholipid bilayer.

Multiple Select

Movement of water molecules across membranes by osmosis involves which of the following? Select all that apply.

• Random movement of particles

• Impermeability of membranes to solutes

• Movement from high solute concentration to low solute concentration

• Differences in solute concentration

Multiple Choice

Which of the following is true about osmosis through aquaporins?

• It is an example of active transport.

• It increases the permeability of the membrane to water.

• It transports solutes across the membrane.

• It decreases the rate of water movement through the membrane.

Open Ended

How do aquaporins facilitate the movement of water across cell membranes, and why is this important for cellular function?

Multiple Choice

Membranes are primarily composed of which type of molecule?

• Proteins

• Carbohydrates

• Phospholipids

• Nucleic acids

Open Ended

What is one question you still have about membranes and membrane transport after today's lesson?