BIOLOGY 1201 EXAM 2 2026 MOCK PAPER
COMPREHENSIVE REVIEW NOTES APLUS
◉ What are the hydrophobic tails of a phospholipid?
Answer: Nonpolar, avoid water
◉ What do phospholipids form in water?
Answer: Bilayer with heads outward, tails inward
◉ What do integral proteins do?
Answer: Span the membrane
◉ What are peripheral proteins?
Answer: Attached to the membrane surface
◉ What are the functions of membrane proteins?
Answer: Transport, enzymatic activity, signal transduction, cell-cell
recognition, intercellular joining, attachment
◉ What role do membrane carbohydrates play?
Answer: Involved in cell-cell recognition
,◉ What is the fluid mosaic model?
Answer: Membrane is flexible with proteins embedded
◉ How do hydrophobic molecules cross the membrane?
Answer: Easily
◉ What do hydrophilic molecules/ions need to cross the
membrane?
Answer: Transport proteins
◉ Why can't ions/polar molecules cross the membrane efficiently?
Answer: Due to charge
◉ What is the order of crossing rates for molecules?
Answer: Small nonpolar > small polar > large polar > ions
◉ What do channel proteins provide?
Answer: Hydrophilic tunnel
◉ What do carrier proteins do?
Answer: Change shape to move molecules
, ◉ What is diffusion?
Answer: Movement from high to low concentration
◉ What is osmosis?
Answer: Diffusion of water
◉ What is facilitated diffusion?
Answer: Passive transport using proteins
◉ What is a concentration gradient?
Answer: Difference in concentration (stores potential energy)
◉ What happens in a hypertonic solution?
Answer: Cell loses water
◉ What happens in a hypotonic solution?
Answer: Cell gains water
◉ What is an isotonic solution?
Answer: No net movement
COMPREHENSIVE REVIEW NOTES APLUS
◉ What are the hydrophobic tails of a phospholipid?
Answer: Nonpolar, avoid water
◉ What do phospholipids form in water?
Answer: Bilayer with heads outward, tails inward
◉ What do integral proteins do?
Answer: Span the membrane
◉ What are peripheral proteins?
Answer: Attached to the membrane surface
◉ What are the functions of membrane proteins?
Answer: Transport, enzymatic activity, signal transduction, cell-cell
recognition, intercellular joining, attachment
◉ What role do membrane carbohydrates play?
Answer: Involved in cell-cell recognition
,◉ What is the fluid mosaic model?
Answer: Membrane is flexible with proteins embedded
◉ How do hydrophobic molecules cross the membrane?
Answer: Easily
◉ What do hydrophilic molecules/ions need to cross the
membrane?
Answer: Transport proteins
◉ Why can't ions/polar molecules cross the membrane efficiently?
Answer: Due to charge
◉ What is the order of crossing rates for molecules?
Answer: Small nonpolar > small polar > large polar > ions
◉ What do channel proteins provide?
Answer: Hydrophilic tunnel
◉ What do carrier proteins do?
Answer: Change shape to move molecules
, ◉ What is diffusion?
Answer: Movement from high to low concentration
◉ What is osmosis?
Answer: Diffusion of water
◉ What is facilitated diffusion?
Answer: Passive transport using proteins
◉ What is a concentration gradient?
Answer: Difference in concentration (stores potential energy)
◉ What happens in a hypertonic solution?
Answer: Cell loses water
◉ What happens in a hypotonic solution?
Answer: Cell gains water
◉ What is an isotonic solution?
Answer: No net movement
