This guy (Bozeman) has some great videos for learning and review; Section I% of Grade Question TypeNumber of Questions Timing Part A: Multiple Choice6390 minuteshalf Part B: Grid-In6 Section II Question TypeNumber of Questions Timing Long Free Response280 minutes minute reading period half Short Free Response6

For the May 2013 Exam Administration and Beyond Exam Content The AP Biology Exam consists of two sections: multiple choice and free response. Both sections include questions that assess students' understanding of the big ideas, enduring understandings, and essential knowledge and their application of these through the science practices. These may include questions on the following: the use of modeling to explain biological principles; the use of mathematical processes to explain concepts; the making of predictions and the justification of phenomena; the implementation of experimental design; and the manipulation and interpretation of data. The exam is 3 hours long and includes both a 90-minute multiple-choice section and a 90-minute free-response section that begins with a mandatory 10-minute reading period. The multiple-choice section accounts for half of the student's exam grade, and the free-response section accounts for the other half. The AP Biology Course and Exam Description, Effective Fall 2012 (.pdf/3.5MB) provides complete details about the exam Section I: Multiple-Choice Section Part A consists of 63 multiple-choice questions that represent the knowledge and science practices outlined in the AP Biology Curriculum Framework that students should understand and be able to apply. Part B includes 6 grid-in questions that require the integration of science and mathematical skills. For the grid-in responses, students will need to calculate the correct answer for each question and enter it in a grid on that section of the answer sheet. Section II: Free-Response Section Students should use the mandatory reading period to read and review the questions and begin planning their responses. This section contains two types of free-response questions (short and long), and the student will have a total of 80 minutes to ocomplete all of the questions.AP Biology Course and Exam Description, Effective Fall 2012

Topics we will attempt to review: (also be sure to read over the test taking hints in the beginning of your Cliff Notes) Review Day 1 1. Cells – cell/plasma membrane structure 2. Photosynthesis and chloroplasts 3. Cell respiration and mitochondria Review Day 2 4. Cell division – mitosis and meiosis 5. Molecular genetics- DNA structure and replication, protein synthesis 6.Animal structure and function- nerve impulse transmission, muscle contraction Review Day 3 7. Plants – repro in flowering plants, plant tropisms and hormones 8. Evolution – natural selection, speciation Review Day 4 9. Animal repro – menstrual cycle 10. Ecology – succession, biochemical cycles 11. If time: go over the 12 labs

AP Review Part 1 –Cell structure –Photosynthesis and chloroplasts –Cell Respiration and mitochondria (chemiosmosis)

1. Cells – cell/plasma membrane (plants, animals and bacteria all have) –Phospholipid bilayer –Hydrophillic heads, hydrophobic tails –Cholesterol –Glycocalyx –Proteins

1. Cells – cell/plasma membrane (plants, animals and bacteria all have) –Phospholipid bilayer, selectively permeable. Separates internal metabolic events from external environment. –Hydrophillic heads form outer faces, hydrophobic tails form center. Pass easily; –Small uncharged polar molecules (H2O, CO2) –Hydrophobic molecules like a O2 and hydrocarbons Don’t pass: –Ions –Large polar water soluble molecules (glucose, proteins, amino acids, nucleic acids) –Cholesterol – provide rigidity in animal cells; in plants, sterols provide rigidity –Glycocalyx – glycolipids and glycoproteins that coat the membrane; provide markers for cell recognition –Proteins scattered throughout membrane make it a fluid mosaic. Proteins can be peripheral proteins – attach to inside or outside; or integral proteins which span across the membrane. Channel proteins Transport proteins Recognition proteins - glycoproteins Adhesion proteins – attach to neighboring cells or provide anchors for internal filaments Receptor proteins – binding sites for hormones and trigger molecules Electron transfer proteins – transfer electrons from one cell to another during chemical reactions

Passive processes –diffusion –facilitated diffusion –osmosis (water diffusion) –filtration –no E needed from cell Active processes –active transport –bulk transport endocytosis –pinocytosis –phagocytosis –receptor mediated endocytosis exocytosis –E needed from cell (ATP)

Passage of Molecules into and out of Cells Uses energy NameDirectionRequirementExamples Passive Processes NoDiffusion Osmosis Toward lower concentration Concentration gradient Lipid soluble molecules, water, gasses NoFacilitated diffusion Toward lower concentration Concentration gradient and carrier Some sugars and amino acids Active Processes YesActive Transport Toward greater concentration CarrierOther sugars, amino acids and ions YesExocytosisToward outsideVesicleMacromolecules YesEndocytosisToward insideVacuoleCells and subcellular material

2. Photosynthesis –Energy transformation in which solar energy is converted to chemical energy –Photosynthetic pigments chlorophyll a and b, carotenoids etc are found in the photosynthetic membranes of chloroplasts (recall that chloroplasts are organelles - a type of plastid) inside of plant cells. Absorb energy from sun – excites electrons Pass energy to special chlorophyll a and b molecules (reaction center) –P680 in PS2 and P700 in PS 1 Eventually end up with glucose (used for cell respiration) and oxygen, which is released to the atmosphere

Equation Summarizing Photosynthesis 6CO H2O + Energy  C6H12O6 + 6H2O + 6O2 Compare to - Cell Respiration C6H12O6 + 6H2O + 6O2  6CO2 + 12H2O + 36 ATP + heat Carbon Dioxide Reduced Water Oxidized Photosynthesis includes: Light dependent reactions PS 2 and PS 1 (non cyclic photophosphorylation) – occur in thylakoid membranes of chloroplasts. Light independent reactions (but needs products from light dependent reactions) – Calvin-Benson Cycle or C3 cycle – occurs in stroma of chloroplasts.

Non cyclic Photophosphorylation –Uses photosystem 2 and photosystem 1(light dependent reactions) to convert the energy in light and in the electrons of H 2 O, to make ATP and NADPH Cyclic Photophosphorylation –More primitive –Can be occurring at same time as non cyclic –Electrons are returned to PS1 instead of making NADPH

Reaction center chlorophyll + Primary electron acceptor = Reaction center e-e-

Light Dependent Reactions Photosystem II –Energy from light excites (passes energy to) antennae complex electrons in pigments (reaction center chlorophyll a - P680) of PS2 in thylakoid membrane of chloroplast.

Light Dependent Reactions Photosystem II –Energy from antennae complex funneled to a reaction center chlorophyll (pigment molecule P680).

Light Dependent Reactions Photosystem II –Reaction center electrons are passed to a primary electron acceptor.

Light Dependent Reactions Photosystem II –Then to electron transport chain where they are passed from carrier to carrier (such as; ferredoxin, cytochrome), losing a little energy each time they are passed.

Light Dependent Reactions Photosystem II –Energy from ETC used to add a P to ADP to make ATP = phosphorylation (hence the name photophosphorylation). This ATP will be used in the light independent reactions.

Light Dependent Reactions Photosystem II –Electrons passed to PS 1 –End Product of PS2 = ATP, which will be used in light independent reactions. –Electrons replaced by photolysis (decomposition by light) H 2 O is split into H + and ½ O 2. These two electrons replace the two lost from PS 2. H ions remain to make gradient O2 lost through stomates

Light Dependent Reactions –Photosystem I Energy from light excites electrons in antennae complex, also receives electron from PS II Energy from antennae complex is funneled to the reaction center chlorophyll a (P700)

Light Dependent Reactions –Photosystem I Reaction center electrons are passed to a primary electron acceptor – different one than PS2 uses.

Light Dependent Reactions –Photosystem I Primary electron acceptor electrons are passed to a short electron transport chain. Note alternate cyclic route (used in cyclic photophosphorylation)

Light Dependent Reactions –Photosystem I At the end of the ETS the 2 electrons are added to NADP + and H + to make NADPH, which stores the considerable energy still left in the electrons. NADPH will be needed for the light independent reactions. Those two electrons need to be replaced.

Light Dependent Reactions –Photosystem I Electrons replaced by photolysis (decomposition by light) H 2 O is split into H + and ½ O 2. These two electrons replace the two lost from PS 2. One of the H + provides the H in NADPH. End product of PS 1 is NADPH

Summary Light Dependent Rx (non cyclic photophosphorylation) –From:

Summary Light Dependent Rx (cyclic photophosphorylation) –From:

Photosynthesis: H + are pumped from stroma into thylakoid, then diffuse back out into stroma. Cell Respiration: H+ are pumped from matrix into intermembrane space, then diffuse back out into matrix.

Light Independent Reactions –Calvin cycle, C3 cycle –Takes place in stroma –Fixes carbon dioxide –Uses 6 CO 2 to make one glucose (C 6 H 12 O 6 ) – 6 turns of cycle. –Can happen without light but needs products from light reactions.

Light Independent Reactions –Calvin Cycle CO 2 reacts with 5 carbon RuBP CO 2 reacts with RuBP  PGA (a 3 carbon compound – phosphoglyceric acid) – need enzyme, rubisco. Most common protein on earth!

Light Independent Reactions –Calvin Cycle ATP and NADPH are reduced to convert PGA to PGAL

Light Independent Reactions –Calvin Cycle ATP used to regenerate RuBP from PGAL 2 of the 12 PGAL (3 C molecule) generated are used to make glucose)6C molecule) – can also make fructose and maltose. –End product of Calvin cycle is ultimately glucose (after 6 turns, using 1 CO 2 for each turn).

Calvin cycle animation: ios100/lectures/calvin.htm ios100/lectures/calvin.htm Note: Diagrams start with either 1, 3, or 6 RuBPs. Starting w 1, cycle has to go around 6x to make one glu. Start w 6, 2x. Start w 12, 1x. PGAL = G3P

Three known modes of photosynthesis –C3 plants – CO2 fixed directly to make PGA –C4 plants – form a C4 molecule prior to the Calvin cycle –CAM plants – form a C4 molecule at night when stomates can open without much water loss

Also look at next few slides –Only in C3 plants : Photorespiration – rubisco (RuBP carboxylase, RuBisCO) fixes (combines it with RuBP) oxygen instead of CO 2, cuts down on efficiency of photosynthesis - –C 4 Photosynthesis - more efficient; hot, dry climates, sugarcane, corn, grass, plus many more, uses PEP carboxylase –CAM photosynthesis –almost like C4;desert plants – can proceed during day even if stomates closed

Photorespiration –Understanding this helps see why C4 and CAM systems are useful –Rubisco can fix either O 2 or CO 2. –When O 2 builds up in the plant (hot/stomates closed), then O 2 gets fixed by rubisco along with CO 2. –This decreases the efficiency of CO 2 fixation. –Process uses a lot of energy without producing many useful end products for the plant.

Photorespiration –Stomates are opened and closed to regulate water exit and CO 2 entry –Hot and dry  close to conserve water, but then less CO 2 available and O 2 builds up –RuBP carboxylase (rubisco) combines O 2 with RuBP (for respiration), instead of CO 2 (for carbon fixation) –Produces one molecule of PGA and releases (eventually) CO 2 –Does not produce any usable energy –Only occurs in C3 plants Photorespiration animation: bios100/lectures/photorespiratio n.htm bios100/lectures/photorespiratio n.htm

CO2 is not produced inside of the chloroplast where it could be useful

C 3 (“regular”) Photosynthesis –Mesophyll cells arranged in parallel layers –Mesophyll cells have well formed chloroplasts (bundle cells don’t) –Only mesophyll cells carry out photosynthesis –Bundle sheath cells do not have chloroplasts –Use enzyme RuBP carboxylase (rubisco) to fix carbon dioxide to RuBP  first detectable molecule is PGA –Wheat, rice, oats

C 4 Photosynthesis –Mesophyll cells not parallel, instead arranged concentrically around bundle sheath cells –Mesophyll cells and bundle cells have chloroplasts Mesophyll cells use enzyme PEPcase (has little attraction to oxygen)to fix carbon dioxide to PEP  first detectable molecule oxaloacetate, a 4 C molecule.Needs energy. PEPcase has less attraction for O2 than RuBP. CO2 passed to bundle cells where it enters the Calvin cycle. –In hot, dry climates have a rate of photosynthesis 2-3X higher than C3 plants would – no photorespiration –Corn, sugarcane, Bermuda grass –No photorespiration – PEPcase does not combine with CO2, so CO2 still delivered to the bundle cells

CAM Photosynthesis –Crassulacean acid metabolism –Happens in most succulent plants –During night use PEPCase forming C 4 molecules (like C4 photo)  which are stored in vacuoles in mesophyll cells –During day (when ATP and NADPH are available)– C 4 molecules are released to the Calvin cycle –Open stomates only at night, conserving water, but limits CO 2 available  less photosynthesis

C4 and CAM animation:

3. Cell Respiration

Cell Respiration –Uses energy from glucose to make ATP –Reaction is just the opposite of photosynthesis 6CO H 2 O + Energy  C 6 H 12 O 6 + 6H 2 O+ 6O2 C 6 H 12 O 6 + 6H 2 O + 6O 2  6CO H 2 O + 36 ATP + heat –Three processes: Glycolysis –Occurs in cytoplasm –Can proceed without oxygen (anaerobic) Krebs Cycle (and transition reaction) –Occurs In mitochondria-matrix –Needs oxygen (aerobic) Electron Transport System and Oxidative Phosphorylation –Occurs in mitochondria-cristae membrane

Cell Respiration –Step 1: Glycolysis First step in respiration Occurs in cytoplasm Doesn’t require oxygen Splits glucose into two pyruvic acid molecules Net gain of 2 ATP (substrate level phosphorylation) and 2NADH

Cell Respiration –Step 2a: Transition Reaction Connects glycolysis to Kreb’s Cycle Pyruvate  acetyl CoA, which enters Krebs cycle Produces 1 NADH and 1 CO 2 Takes place in matrix of mitochondria

Cell Respiration –Step 2b: Kreb’s Cycle Series of reactions in a repeating cycle, takes place in matrix of mitochondria Does need oxygen (aerobic) Starts with acetyl CoA Each “turn” of the Krebs cycle produces –1 molecule ATP –2 molecules of CO 2 –4 pairs of hydrogen atoms (most of energy from glucose carried here) »Hydrogen atoms will later be picked up by NAD + and FAD to make NADH2 and FADH2

Cell Respiration –Step 3: Electron Transport System (oxidative phosphorylation) Takes place in the cristae of mitochondria Most of energy of cell respiration is produced here Series of protein molecules in membrane NADH + H + and FADH 2 deliver H + and electrons to system Ultimately ATP is formed (by chemiosmosis) –3 for each NADH –2 for each FAD

Cell Respiration –ETS (cont) Oxygen is the final H + and electron acceptor ½ O 2 combines with 2H + and 2 electrons to make water Ultimately 36 ATP are formed by cell respiration

Cell Respiration –Chemiosmosis Electrons from NADH and FAD lose energy as they pass along the ETC That energy is used to phosphorylate ADP  ATP Chemiosmosis is how that occurs

Chemiosmosis –Electrochemical gradient of H ions used to produce ATP –Of the 36 molecules of ATP produced from one molecule of glucose (being completely metabolized), 32 come from electron transport system’s oxidative phosphorilation.

Chemiosmosis –Electrons from NADH (and FADH 2 ) enter ETS in cristae membrane of mito –H + from NADH and FADH 2 are pumped from matrix to intermembrane space –Creates a pH, chemical and electrical gradient that forces H + to flow through ATP synthase complex back into matrix –Protons passing through the complex provide the energy to add P (phophorylate) to ADP making ATP, which then flows through an ATP channel protein into intermenbrane space, then out of the mito

Chemiosmosis –Electrochemical gradient of H ions used to produce ATP –Of the 36 molecules of ATP produced from one molecule of glucose (being completely metabolized), 32 come from electron transport system’s oxidative phosphorilation.