Download S10 Key BLM 8-6 7 - Cochrane High School

BLM 8-6, Types of Transport Across Cell Membranes/Reinforcement
Goal: Students review their understanding of the various types of transport across cell membranes.
Answers:
A. Facilitated diffusion using carrier proteins: Facilitated diffusion works in the same direction as the
concentration gradient. Carrier proteins recognize specific molecules because of their size and shape.
The molecule to be carried fits into a groove in the protein, much like a lock and key.
B. Diffusion (O2) and osmosis (H2O): Diffusion is the movement of particles from an area of high
concentration to an area of low concentration. Osmosis is the diffusion of water molecules.
C. Facilitated diffusion using channel proteins: Facilitated diffusion works in the same direction as the
concentration gradient. Channel proteins fill tunnel-like pores in the membrane and recognize
molecules by their electrical charge.
D. Active transport: Active transport works against the concentration gradient and requires energy.
BLM 8-7, The Role of Cell Membranes in Endocytosis and
Exocytosis/Assessment
Goal: Students review their understanding of endocytosis and exocytosis.
Answers
1. A. Phagocytosis is a type of endocytosis. It is used to
ingest food and other solids (“cell eating”).
The
cell membrane forms a pocket around the
substance to be transported.
B. Pinocytosis is also a type of endocytosis. This
process is used to ingest fluids (cell
“drinking”). The cell membrane forms a pocket around the
substance to be transported.
C. Exocytosis occurs to dispose of wastes or to secrete cell products outside of the cell.
D. solid
E. vesicle
F. solute
G. cell membrane
H. secreted solute
2. Endocytosis is used when substances can’t be moved by either active or passive transport.
3. Receptor-mediated endocytosis is when membrane proteins act like receptors to recognize specific
compounds or cells in the environment. When a receptor recognizes an item for transport, the receptor
binds to it and triggers endocytosis.