Exploring the Plasma Membrane in IB Biology

What is the modern term used for the cell membrane?

• Mitochondrial membrane

• Plasma membrane

• Nuclear membrane

• Cytoplasmic membrane

Which organelle's membrane is made up of the same materials as the plasma membrane?

• Nucleus

• Mitochondria

• Golgi apparatus

• Ribosome

What is the main structural component of the plasma membrane?

• Proteins

• Carbohydrates

• Phospholipids

• Nucleic acids

What characteristic do the tails of phospholipids have?

• Hydrophilic

• Hydrophobic

• Amphipathic

• Polar

What term describes the plasma membrane's ability to allow some substances to pass through while blocking others?

• Impermeable

• Permeable

• Non-permeable

• Semipermeable

What type of protein spans the entire plasma membrane?

• Transmembrane protein

• Extrinsic protein

• Peripheral protein

• Surface protein

What is the function of proteins that do not extend through the plasma membrane?

• Act as electron carriers

• Act as channels

• Act as pumps

• Act as hormone binding sites

What role does cholesterol play in the plasma membrane?

• Increases fluidity

• Decreases fluidity

• Acts as a carbohydrate

• Acts as a protein

What is a glycoprotein composed of?

• Protein and nucleic acid

• Protein and lipid

• Carbohydrate and lipid

• Carbohydrate and protein

Why is the plasma membrane described as a 'fluid mosaic model'?

• Because it is impermeable

• Because it is dynamic and has a mosaic of different molecules

• Because it is static and rigid

• Because it is composed of a single type of molecule