AP BIO: Unit Two Study Guide
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Know the key differences between Prokaryotic, Eukaryotic Animal, and Eukaryotic Plant cells.
Know the function of and be able to label any cell diagram with the following organelles: cell wall, plasma membrane,
ribosome, smooth ER, rough ER, golgi, mitochondria, lysosome, nucleus, peroxisome, chloroplast, cytoskeleton, vacuole,
and centrioles.
Fluid Mosaic Model: the plasma membrane is a selectively permeable phospholipid bilayer with proteins of various lengths
and sizes interspersed with cholesterol among the phospholipids.
Integral proteins are implanted within the lipid bilayer of the plasma membrane
Peripheral proteins are attached to the exterior of the membrane
Diffusion is the passive movement of a substance down its concentration gradient (from high concentration to low
concentration)
Osmosis is the diffusion of water from the side of low solute concentration to the side of high solute concentration
(hypotonic to hypertonic)
Facilitated diffusion is assisted transport of particles across the membrane by proteins, but no energy input is needed
Active transport is the movement of substances against the concentration gradient (from low to high) and it requires
energy input from the cell in the form of ATP
Endocytosis is the movement of particles into a cell through the use of vesicles (phagocytosis and pinocytosis)
Exocytosis is the process by which particles are ejected from the cell through the use of vesicles (endocytosis in reverse)
If you remember one thing from glycolysis, remember ONE glucose molecule yields 2 PYRUVATE, 2 ATP, and 2 NADH.
If you remember one thing from the Krebs cycle, remember each pyruvate yields 4 NADH, 1 FADH2, and 1 ATP
If you remember one thing from fermentation remember that yeast, fungi, and bacteria produce ethanol and humans
produce lactic acid (but only during an oxygen deficit)
Aerobic respiration consists of glycolysis  Krebs cycle  oxidative phosphorylation  36 ATP per glucose molecule
Anaerobic respiration (fermentation) consists of glycolysis  regenerate NAD+  2 ATP per glucose molecule
Respiration process in three parts
o Glycolysis is the conversion of 1 glucose molecule into 2 pyruvate, 2 ATP, and 2 NADH; occurs in the cytoplasm,
and in both aerobic and anaerobic respiration; must have NAD+ to occur; total energy production to this point is 2
ATP + 2 NADH
o Krebs cycle is the conversion of 1 pyruvate molecule into 4 NADH, 1 FADH 2, 1 ATP, H2O, and CO2; occurs twice for
each glucose to yield 8 NADH, 2 FADH2, and 2 ATP; occurs in mitochondria; total energy production to this point is
4 ATP + 10 NADH + 2 FADH2
o Oxidative phosphorylation is the production of large amounts of ATP from NADH and FADH 2; total energy
production to this point per glucose molecule is 38 ATP (but 2 ATP are used in the process) so 36 ATP is the net
total
 Occurs in the mitochondria; requires the presence of oxygen to proceed
 NADH and FADH2 pass their electrons down the electron transport chain to produce ATP
 Each NADH can produce up to 3 ATP; each FADH2 can produce up to 2 ATP
 One oxygen atom (1/2 of O2) is the final acceptor in the electron transport chain
 Movement of electrons down the chain leads to movement of H + out of the matrix
 Ox-phos regenerates NAD+ so that glycolysis and the Krebs cycle can continue
Chemiosmosis is the coupling of the movement of electrons down the ETC with the formation of ATP using the driving force
provided by the proton gradient; occurs in both cell respiration and photosynthesis to produce ATP
ATP synthase is the enzyme responsible for using protons to actually produce ATP from ADP
Fermentation in general is any process that regenerates NAD+ so glycolysis can begin again
o Occurs in the absence of oxygen
o Begins with glycolysis: 2 ATP, 2 pyruvate, and 2 NADH are produced from 1 glucose molecule
o Because there is no oxygen to accept the electron energy on the chain, there is a shortage of NAD +, which prevents
glycolysis from continuing unless fermentation regenerates the NAD +
Alcoholic fermentation occurs in fungi, yeast, and bacteria; causes conversion of pyruvate to ethanol
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Lactic acid fermentation occurs in human and animal muscle cells: causes conversion of pyruvate to lactate; causes
cramping or burning sensation when oxygen runs low in muscle cells
Know the general chemical reactions for both respiration and photosynthesis
Photosynthesis is the process by which plants use the energy from light to generate sugar; it occurs in the chloroplasts;
more specifically, the light reactions happen in the thylakoid and the Calvin cycle happens in the stroma
Autotrophs are self-nourishing organisms that are also known as producers (e.g. plants)
Heterotrophs are organisms that must consume other organisms to obtain energy; also called consumers (e.g. animals)
Transpiration is the loss of water via evaporation through the stomata
Photophosphorylation is the process by which ATP is made during the light reactions
Photolysis is the process by which water is split into hydrogen ions and oxygen atoms in the light reactions
Stomata are the structures through which CO2 enters a leaf, and water vapor and oxygen leave a leaf
Pigments are molecules that absorb light of a particular wavelength (chlorophylls, carotenoids, and phycobilins)
There are three types of photosynthesis reactions
o Noncyclic light-dependent reactions
 Occur in thylakoid membrane of the chloroplast
 Inputs are light and water
 Light strikes photosystem II (P680)
 Electrons pass along until they reach the primary electron acceptor
 Photolysis occurs – H2O is split to H+ and O2
 Electrons pass down an ETC to P700 (photosystem I), forming ATP by chemiosmosis
 Electrons of P700 pass down another ETC to produce NADPH
 The three products of the light reactions are NADPH, ATP, and O 2
 Oxygen produced comes from H2O and is mostly released through stomata as waste (and ultimately used
as a reactant in aerobic respiration; part of the carbon cycle)
o Cyclic light-dependent reactions
 Occur in thylakoid membrane
 Only involves photosystem I; no photosystem II
 ATP is the only product of these reactions
 No NADPH or oxygen are produced
 These reactions exist because the Calvin cycle uses more ATP than NADPH; this is how the difference is
made up
o Light-independent reactions (Calvin cycle) aka Dark Reactions
 Occurs in the stroma of chloroplast
 Inputs are NADPH, ATP, and CO2
 First step is carbon fixation, which is catalyzed by an enzyme named rubisco
 A series of reactions lead to the production of NADP+, ADP, and sugar
 More ATP is used than NADPH, which creates the need for the cyclic light reactions
 The carbon of the sugar product comes from CO2. (The sugar is then used to provide energy reactants for
respiration in both plants and animals; again, the carbon cycle)
C4 plants have adapted their photosynthetic process to more efficiently handle hot and dry conditions. C4 photosynthesis is
a process that first converts CO2 into a 4-carbon molecule in the mesophyll cells, converts that product to malate, and then
shuttles it to the bundle sheath cells, where the malate releases CO2 and rubisco picks it up as if all were normal; (a
physical separation of the light and dark reactions)
CAM plants close their stomata during the day, collect CO2 at night, and store the CO2 in the form of acids until it is needed
during the day for photosynthesis; (a temporal separation of the light and dark reactions)
Study your notes and your R&R. Powerpoints/videos can be found on my website to help you review.
Test Set-Up: Approximately 30-50 multiple choice questions (probably closer to 30 for this time) and one long or two short freeresponse essay question that will be given to you the night before (prompt only), but must be written in class without notes.