AP Biology Review Session 2 Concept Check The

AP Biology Review Session 2

Concept Check • The cell is sometimes described as a protein factory. Using the cell-asfactory analogy, which of the following accurately describes the functions of the endomembrane system? 1) The ribosomes on the rough endoplasmic reticulum are analogous to a production line in a factory. 2) The golgi apparatus is analogous to the packaging and shipping department. 3) The nucleus is analogous to management offices. 4) All of the above.

Concept Check • The three domains of life described by biologists today include the bacteria, the archaea and the eukarya (all other forms of life). What is the principle difference between the eukarya or eukaryotes and the prokaryotes (archaea and bacteria)? • The prokaryotes do not have a plasma membrane surrounding the cell. • The prokaryotes use RNA and not DNA to pass on the genetic message. • The eukaryotes have the interior of the cell divided by internal membranes into specialized compartments. • The eukaryotes engage in cellular metabolism while the prokaryotes do not.

Chapter 4 $100 Question • A _____ is an example of a unicellular organism. • • a. cat b. pine tree c. fish d. protist ANSWER

Chapter 4 $200 Question • Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell, they _____. • • a. lack a nucleus b. have a smaller nucleus c. lack a plasma membrane d. Have more internal membranous compartments ANSWER

Chapter 4 $300 Question • _____ are the major lipids of plasma membranes. • • a. Triglycerides b. Phospholipids c. Fatty acids d. Steroids ANSWER

Chapter 4 $400 Question • Which of these pairs of organelles are responsible for energy conversion? • • a. mitochondrion and chloroplast b. vacuole and ribosome c. centriole and lysosome d. Golgi apparatus and smooth endoplasmic reticulum ANSWER

Chapter 4 $500 Question • Information is transferred from the cell nucleus to ribosomes via the molecule _____. • • a. RNA b. r. ER c. s. ER d. DNA ANSWER

a. l. b. c. k. j. i. h. d. g. e. f.

1. Describe microscopes and their importance in viewing cellular structure 2. Distinguish between prokaryotic and eukaryotic cells 3. Describe the structure of cell membranes and how membrane structure relates to function 4. Discuss ways that cellular organelles are involved in the manufacture and breakdown of important cellular molecules 5. List cell structures involved in manufacture and breakdown of important cellular materials 6. Describe the function of each cellular organelle that is involved in manufacture and breakdown of important cellular materials 7. List cell structures involved in energy conversion 8. Describe the function of each cellular organelle that is involved in energy conversion 9. List cell structures involved in internal and external support of cells 10. Describe the function of each cellular organelle that is involved in internal and external support of the cell Copyright © 2009 Pearson Education, Inc.

Concept Check • This diagram represents osmosis of water across a semipermeable membrane. The Utube on the right shows the results of the osmosis. What could you do to level the solutions in the two sides of the right hand U-tube? • Add more water to the left hand side. • Add more water to the right hand side. • Add more solute to the left hand side. • Add more solute to the right hand side.

Concept Check • Membranes organize cell activities. The proteins imbedded in the membranes are essential to their function. These membrane proteins have properties that allow them to “float” in the membrane. Which of the following describe those properties? • The surface region of the protein in the interior of the membrane is mostly hydrophobic. • The surface region of the protein in the interior of the membrane is mostly hydrophillic. • The surface region exposed to the outer environment is hydrophobic. • The surface region exposed to the interior environment is hydrophobic.

Concept Check • Enzymes catalyze the many reactions in a cell. There are hundreds of different enzymes in a cell—each with a unique three-dimensional shape. Why do cells have so many different enzymes? • Each enzyme molecule can only be used • • • once. The shape of enzyme’s active site generally fits a specific substrate. The substrate molecules react with enzymes to create new enzymes. Enzymes are randomly produced. With thousands of different shapes—one is likely to work.

Chapter 5 $100 Question • Which of the following is a measure of disorder? • • a. entropy b. kinetic energy c. potential energy d. respiration ANSWER

Chapter 5 $200 Question • A(n) _______ is the amount of energy that raises the temperature of 1 g of water by 1° C. • • a. calorie b. ATP c. entropy d. enzyme ANSWER

Chapter 5 $300 Question • Molecules of food and gasoline contain a special form of potential energy called _____ energy, due to the arrangement of their atoms. • • a. kinetic b. ionic c. covalent d. chemical ANSWER

Chapter 5 $400 Question • Enzymes increase the rate of a reaction by ____. • a. decreasing activation energy • b. changing the p. H • c. increasing the temperature of the substances • d. contributing water to the reaction ANSWER

Chapter 5 $500 Question • Osmosis is _______. • a. the diffusion of nonpolar materials • b. the diffusion of water across a semi-permeable membrane • c. the diffusion of a solute • d. active transport ANSWER

Diffusion Requires no energy Requires energy Passive transport Active transport Facilitated diffusion Higher solute concentration Osmosis Higher water concentration Higher solute concentration Solute Water Lower solute concentration Lower water concentration Lower solute concentration

ATP cycle Energy from exergonic reactions Energy for endergonic reactions

Molecules cross cell membranes by by passive transport may be (a) moving down moving against requires (b) uses diffusion of (c) (d) uses of polar molecules and ions (e)

c. b. a. d. f. e.

You should now be able to 1. 2. 3. 4. 5. 6. 7. 8. Describe the cell membrane within the context of the fluid mosaic model Explain how spontaneous formation of a membrane could have been important in the origin of life Describe the passage of materials across a membrane with no energy expenditure Explain how osmosis plays a role in maintenance of a cell Explain how an imbalance in water between the cell and its environment affects the cell Describe membrane proteins that facilitate transport of materials across the cell membrane without expenditure of energy Discuss how energy-requiring transport proteins move substances across the cell membrane Distinguish between exocytosis and endocytosis and list similarities between the two Copyright © 2009 Pearson Education, Inc.

You should now be able to 9. Explain how energy is transformed during life processes 10. Define the two laws of thermodynamics and explain how they relate to biological systems 11. Explain how a chemical reaction can either release energy or store energy 12. Describe ATP and explain why it is considered to be the energy currency of a cell 13. Define enzyme and explain how enzymes cause a chemical reaction to speed up 14. Discuss the specificity of enzymes 15. Distinguish between competitive inhibitors and noncompetitive inhibitors Copyright © 2009 Pearson Education, Inc.

Concept Check • Some prokaryotic and all eukaryotic cells use oxygen to harvest energy from food molecules? In what form is that energy available to power cell work? • Heat and light. • Glucose molecules. • Fat molecules. • ATP molecules.

Concept Check • Fat molecules store 9 Kcal per gram. There about 454 grams in a pound of fat so that means that one pound of fat stores about 4, 000 Kcal of energy. Based on the chart of energy consumption, which of the following would “burn off” a pound of fat, assuming your normal activities consumed calories equal to the rate of your calorie intake? • Running 7 miles • Swimming 2 miles • Walking 27 miles • Running about 40 miles

Concept Check • The figure above represents an overview of the different processes of cellular respiration. Which of the following correctly identifies the different processes? • 1. Glycolysis; 2. Electron transport chain; 3. Krebs cycle • 1. Glycolysis; 2. Krebs cycle; 3. Electron transport chain • 1. Krebs cycle; 2. Electron transport chain; 3. Glycolysis • 1. Electron transport chain; 2. Glycolysis; 3. Krebs cycle

Concept Check The figure above represents an overview of the different entry pathways to cellular respiration when different macromolecules are digested for energy production. Why are none of the digestive products entering the electron transport chain, directly? • • The electron transport chain is too deeply embedded in the mitochondria. The electron transport chain only receives electrons carried by reduced electron carrier molecules such as NADH. The electron transport chain only receives electrons carried by oxidized electron carrier molecules such as NAD+. The electron transport chain does not produce ATP.

Chapter 6 $100 Question • The molecule _____ is the main source of energy used to drive chemical reactions in cells. • • a. lactic acid b. ATP c. carbon dioxide d. DNA ANSWER

Chapter 6 $200 Question • ______ is the anaerobic harvest of food energy. • • a. Electron transport b. Cellular respiration c. Photosynthesis d. Fermentation ANSWER

Chapter 6 $300 Question • Where in the cell does glycolysis occur? • • a. outside the mitochondria b. in the endoplasmic reticulum c. in the fluid of the mitochondria d. on the outer mitochondrial membrane ANSWER

Chapter 6 $400 Question • The final electron acceptor of aerobic respiration is ____. • • a. ATP b. oxygen c. carbon dioxide d. lactic acid ANSWER

Chapter 6 $500 Question • What must pyruvic acid be converted to before it can enter the citric acid cycle? • • a. acetyl Co. A b. lactic acid c. ethyl alcohol d. NADH ANSWER

ATP needed to drive biosynthesis ATP CITRIC ACID CYCLE GLUCOSE SYNTHESIS Acetyl Co. A Pyruvate G 3 P Glucose Amino groups Amino acids Proteins Fatty acids Glycerol Fats Cells, tissues, organisms Sugars Carbohydrates

Cytoplasm NADH Mitochondrion NADH and FADH 2 Glycolysis Glucose Pyruvate CO 2 ATP Oxidative phosphorylation (Electron Transport and Chemiosmosis) Citric acid cycle CO 2 ATP

Cellular respiration generates has three stages oxidizes uses ATP energy for produce some glucose and organic fuels (a) produces many C 6 H 12 O 6 (b) (d) to pull electrons down (c) cellular work by process called H+ diffuse through ATP synthase chemiosmosis uses (f) uses (e) pumps H+ to create H+ gradient to

You should now be able to 1. 2. 3. 4. 5. 6. 7. 8. Explain how photosynthesis and cellular respiration are necessary to provide energy that is required to sustain your life Explain why breathing is necessary to support cellular respiration Describe how cellular respiration produces energy that can be stored in ATP Explain why ATP is required for human activities Describe the process of energy production from movement of electrons List and describe three main stages of cellular respiration Describe the major steps of glycolysis and explain why glycolysis is considered to be a metabolic pathway Explain how pyruvate is altered to enter the citric acid cycle and why coenzymes are important to the process Copyright © 2009 Pearson Education, Inc.

You should now be able to 9. 10. 11. 12. 13. 14. 15. 16. Describe the citric acid cycle as a metabolic pathway designed for generating additional energy from glucose Discuss the importance of oxidative phosphorylation in producing ATP Describe useful applications of poisons that interrupt critical steps in cellular respiration Review the steps in oxidation of a glucose molecule aerobically Compare respiration and fermentation Provide evidence that glycolysis evolved early in the history of life on Earth Provide criteria that a molecule must possess to be considered a fuel for cellular respiration Discuss the mechanisms that cells use to biosynthesize cell components from food Copyright © 2009 Pearson Education, Inc.

Concept Check • This is the summary equation for the process of photosynthesis. This reaction • is endergonic. • is exergonic. • has an equal amount of energy in the reactants and the products. • is catabolic.

Concept Check • Both cellular respiration and photosynthesis rely on electron transport chains embedded in membranes to produce ATP molecules. Which of the following correctly describes the difference between the two types of electron transport chains? • In cellular respiration the electron source is water and the final • • • electron destination is oxygen. In cellular respiration the electron source is the hydrogens in energy rich food and the final electron destination is oxygen. In photosynthesis the electron source is water and the final destination is oxygen. Both 2 and 3.

Concept Check • When a photon of the correct energy is absorbed by a photosystem, an electron is energized and transferred to a primary electron acceptor. This creates an electron “hole”. How is the missing electron replaced? • Electrons removed from glucose replace the missing electrons. • Electrons from hydrogen made available by splitting water replace the missing electrons. 1) The replacement electrons come from NADPH. 2) The electrons come from ATP.

Concept Check • Imagine that you have planted bean seedlings (C 3) and corn seedlings (C 4) in an artificial soil and sealed them in an aquarium. The aquarium has plenty of light, nutrients and water but a given volume of air. Based on your knowledge of photorespiration which of the following are most likely? • Both kinds of plants should do equally • • • well. As the plants photosynthesize the carbon dioxide levels will fall giving the C 3 plants the advantage. As the plants photosynthesize the carbon dioxide levels will fall giving the C 4 plants the advantage. The results are unpredictable. C 3 plant, low CO 2 C 4 plant, low CO 2

Chapter 7 $100 Question • Which of the following is an autotroph? • • a. mushroom b. honeybee c. mountain lion d. pine tree ANSWER

Chapter 7 $200 Question • In which organelle does photosynthesis occur? • • a. chloroplast b. mitochondrion c. nucleus d. smooth endoplasmic reticulum ANSWER

Chapter 7 $300 Question • _____ is the source of the oxygen gas released by a photosystem. • • a. NADPH b. Water c. Carbon dioxide d. Chlorophyll a ANSWER

Chapter 7 $400 Question • The light reactions of photosynthesis take place in the____. • • a. stroma b. thylakoid membrane c. cytosol d. cristae ANSWER

Chapter 7 $500 Question • _____, produced during the Calvin cycle, is the raw material plants use to make necessary organic molecules. • • a. Glucose b. Carbon dioxide c. Sucrose d. G 3 P ANSWER

Light H 2 O Chloroplast CO 2 Stroma NADP+ Thylakoid membranes ADP � P Light reactions ATP Calvin cycle NADPH O 2 Sugar

Mitochondrion structure Chloroplast structure Intermembrane space H+ c. Membrane Matrix d. a. b. e.

Photosynthesis converts includes both (a) (b) (c) to in which chemical energy in which light-excited electrons of chlorophyll H 2 O is split CO 2 is fixed to Ru. BP and then and (d) (h) reduce NADP+ to are passed down using (f) (e) to produce producing (g) by chemiosmosis sugar (G 3 P)

You should now be able to 1. 2. 3. Explain the value of autotrophs as producers Provide a general description of photosynthesis in chloroplasts Explain how plants are able to produce oxygen as a product of photosynthesis 4. Contrast photosynthesis to respiration in terms of redox reactions 5. Describe the importance of visible radiation to photosynthesis 6. Describe plant photosystems and their function in photosynthesis 7. Describe the linkage (connection) between the two plant photosystems 8. Describe how chemiosmosis powers ATP synthesis in plants 9. Discuss the Calvin cycle and how it uses ATP and NADPH 10. Describe two plant adaptations that save water in hot, dry climates 11. Detail how photosynthesis could help moderate globing warming 12. Discuss the importance of the Earth’s protective ozone layer Copyright © 2009 Pearson Education, Inc.