Midterm Study Guide KEY p. 2
Cellular Transport
Vocab
 Diffusion – process where molecules move from high to low concentration without energy
 Osmosis – process where water molecules move from high to low concentration without energy
 Facilitated diffusion – process where molecules move from high to low concentration though a
protein channel
 Active transport – process where molecules move from low to high concentration with energy
 Passive transport – type of transport where no energy is required (high to low)
 Concentration gradient – where there is a change in the amount of solute in a solution
 Sodium-Potassium Pump – type of active transport where Na+ moves out of the cell and K+ into
the cell
 Endocytosis – type of active transport where molecules enter the cell via vesicles
 Exocytosis – type of active transport where molecules exit the cell via vesicles
 Pinocytosis – type of endocytosis where liquids enter the cell via vesicles
 Phagocytosis – type of endocytosis where solid particles enter the cell via vesicles
 Calcium ion channel – protein pump where calcium ions pass through
Questions
1. What is the difference between a hypertonic, hypotonic, and an isotonic solution?
Hypertonic  higher concentration outside the cell
Isotonic  same concentration outside and inside the cell
Hypotonic  lower concentration outside the cell
2. What happens to a plant cell when placed in a hypertonic solution? Hypotonic solution?
Hypertonic  central vacuole will release excess water and cell membrane may peel from
the cell wall to shrink (turgor pressure is LOW in the vacuole)
Hypotonic  central vacuole will take in excess water until the cell membrane pushes onto
the cell wall and causing the cell to bulge (turgor pressure is HIGH in the vacuole)
3. What happens to an animal cell when placed in a hypertonic solution? Hypotonic solution?
Hypertonic  cell will shrink
Hypotonic  cell will swell (possibly burst)
4. What is selective permeability and how is the plasma membrane selectively permeable?
Selectively permeable means the cell membrane has the ability to choose what is allowed to
enter and leave the cell. Our plasma membrane will only allow certain solutions and
molecule into the cell using specific types of cellular transport.
Photosynthesis
Vocab
 Chemiosmosis – process of making ATP molecules
Questions
1. What is the role of chlorophyll in photosynthesis?
Chlorophyll absorbs the light energy from the sun and transfers it to chemical energy
during the photosystem reactions.
2. What happens during the light-dependent reactions? During the light-independent reactions?
Light dependent  occur in the thylakoid membranes of the chloroplast. Require sunlight
in order to occur. Photosystems I and II take place during these reactions. Oxygen is made
and the ETC allows for chemiosmosis to take place producing ATP.
3. Why do we see the color green when light is absorbed by chlorophyll?
Chlorophyll absorbs all colors from light except for green. Green is reflected therefore that
is the color you see.
4. What are the products of each of the reactions of photosynthesis?
Photosystem I & II  O2 and ATP
Calvin cycle  glucose (C6H12O6)
5. Compare & Contrast C3, C4, and CAM plants
C3 and C4 plants usually have their stomata open during the day and CAM plants only have
their stomata open at night time to avoid drying out.
6. What are the factors that affect the rate of photosynthesis, and how do they affect them?
Temperature  Increases the rate to a certain point then decreases if too hot
CO2 concentration  Increases the rate to a certain point, then stays the same
Light intensity  Increases the rate to a certain point, then stays the same
7. What is the source of oxygen produced during photosynthesis?
When water is split during Photosystem II.
Cellular Respiration
Vocab
 ATP – form of energy in our cells
 Glycolysis – process where glucose molecules are broken down into pyruvic acid
 Fermentation – process of respiration where oxygen is not present (alcoholic or lactic acid)
Questions
1. How are photosynthesis and cellular respiration a circular process?
The products of one reaction are the starting reactants of the other. They complement each
other.
2. What are the stages of aerobic respiration?
Aerobic respiration is broken down into Glycolysis and Cellular Respiration (Kreb’s Cycle &
Electron Transport Chain).
3. What are the two types of fermentation? What are their products?
The two types of fermentation are lactic acid fermentation and alcoholic fermentation. The
products are lactic acid and alcohol respectively.
4. What is the product of glycolysis?
The product of glycolysis are 2 pyruvic acid molecules that will be used in the Kreb’s cycle.
5. What process produces the most amount of ATP?
The electron transport chain.