CAMPBELL BIOLOGY IN FOCUS CHAPTER 43
ACTUAL TEST PAPER QUESTIONS AND
SOLUTIONS GRADED A+
◉ Amphipathic.
Answer: Having a hydrophilic and hydrophobic region
◉ Fluid mosaic model.
Answer: Model that describes the membrane as a mosaic of protein
molecules bobbing in a fluid bilayer of phospholipids
◉ At high temperatures, what kind of lipids are used?.
Answer: Saturated hydrocarbon tails
◉ What is the role of cholesterol in membrane fluidity?.
Answer: At high temperatures, it makes the membrane less fluid; at
low temperatures, it maintains fluidity.
◉ Integral proteins.
Answer: Proteins that penetrate the hydrophobic interior of the lipid
bilayer
, ◉ Transmembrane proteins.
Answer: Proteins that span the membrane
◉ Peripheral proteins.
Answer: Proteins not embedded in the lipid bilayer; loosely bound to
the surface of the membrane
◉ What are functions of membrane proteins?.
Answer: Transport, enzymetic activity, signal transduction, cell-cell
recognition, intercellular joining, attachment to the cytoskeleton and
extracellular matrix (ECM)
◉ Glycolipids.
Answer: Membrane carbohydrates that are covalently bonded to
lipids
◉ Glycoproteins.
Answer: Membrane carbohydrates that are covalently bonded to
proteins
◉ How permeable is the plasma membrane?.
Answer: Small nonpolar molecules cross easily; polar molecules
don't.
ACTUAL TEST PAPER QUESTIONS AND
SOLUTIONS GRADED A+
◉ Amphipathic.
Answer: Having a hydrophilic and hydrophobic region
◉ Fluid mosaic model.
Answer: Model that describes the membrane as a mosaic of protein
molecules bobbing in a fluid bilayer of phospholipids
◉ At high temperatures, what kind of lipids are used?.
Answer: Saturated hydrocarbon tails
◉ What is the role of cholesterol in membrane fluidity?.
Answer: At high temperatures, it makes the membrane less fluid; at
low temperatures, it maintains fluidity.
◉ Integral proteins.
Answer: Proteins that penetrate the hydrophobic interior of the lipid
bilayer
, ◉ Transmembrane proteins.
Answer: Proteins that span the membrane
◉ Peripheral proteins.
Answer: Proteins not embedded in the lipid bilayer; loosely bound to
the surface of the membrane
◉ What are functions of membrane proteins?.
Answer: Transport, enzymetic activity, signal transduction, cell-cell
recognition, intercellular joining, attachment to the cytoskeleton and
extracellular matrix (ECM)
◉ Glycolipids.
Answer: Membrane carbohydrates that are covalently bonded to
lipids
◉ Glycoproteins.
Answer: Membrane carbohydrates that are covalently bonded to
proteins
◉ How permeable is the plasma membrane?.
Answer: Small nonpolar molecules cross easily; polar molecules
don't.
