AP Biology Review Session 2

Concept Check•The cell is sometimes described as a protein factory. Using the cell-as-factory 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. rER• c. sER• d. DNA

ANSWER

a.

b.

c.

d.

e.

f.

g.

h.

i.

j.

k.

l.

1. Describe microscopes and their importance in viewing cellular structure2. Distinguish between prokaryotic and eukaryotic cells3. Describe the structure of cell membranes and how membrane structure relates to

function4. Discuss ways that cellular organelles are involved in the manufacture and

breakdown of important cellular molecules5. List cell structures involved in manufacture and breakdown of important cellular

materials6. Describe the function of each cellular organelle that is involved in manufacture

and breakdown of important cellular materials7. List cell structures involved in energy conversion8. Describe the function of each cellular organelle that is involved in energy

conversion9. List cell structures involved in internal and external support of cells10. Describe the function of each cellular organelle that is involved in internal and

external support of the cell

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Concept Check•This diagram represents osmosis of water across a semipermeable membrane. The U-tube 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 pH• 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

Passive transport

Higher solute concentration

Facilitateddiffusion

OsmosisHigher waterconcentration

Higher soluteconcentration

Requires energy

Active transport

Solute

Water

Lower soluteconcentration

Lower waterconcentration

Lower soluteconcentration

ATP cycle

Energy fromexergonicreactions

Energy forendergonicreactions

Molecules crosscell membranes

passivetransport

by by

may be movingdown

movingagainst

requires

uses

diffusion

of

polar moleculesand ions

uses

of

(a)

(c)

(d)

(b)

(e)

a.

b.c.

d.

e.

f.

1. Describe the cell membrane within the context of the fluid mosaic model

2. Explain how spontaneous formation of a membrane could have been important in the origin of life

3. Describe the passage of materials across a membrane with no energy expenditure

4. Explain how osmosis plays a role in maintenance of a cell5. Explain how an imbalance in water between the cell and its environment

affects the cell6. Describe membrane proteins that facilitate transport of materials across

the cell membrane without expenditure of energy7. Discuss how energy-requiring transport proteins move substances across

the cell membrane8. Distinguish between exocytosis and endocytosis and list similarities

between the two

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You should now be able to

9. Explain how energy is transformed during life processes10. 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 energy12. Describe ATP and explain why it is considered to be the

energy currency of a cell13. Define enzyme and explain how enzymes cause a

chemical reaction to speed up14. Discuss the specificity of enzymes15. Distinguish between competitive inhibitors and

noncompetitive inhibitorsCopyright © 2009 Pearson Education, Inc.

You should now be able to

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.

•Fat molecules store 9 Kcal per gram. There are 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

Concept Check

•The figure above represents an overview of the different processesof cellular respiration. Which of the following correctly identifies thedifferent 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 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.

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?

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 CoA• b. lactic acid• c. ethyl alcohol• d. NADH

ANSWER

Cells, tissues, organisms

Proteins Fats Carbohydrates

Glucose

ATP needed to drive biosynthesis

CITRICACID

CYCLE

AcetylCoA

GLUCOSE SYNTHESIS

Pyruvate

Amino acids Glycerol SugarsFatty acids

Amino groups

G3P

ATP

Cytoplasm

GlucoseOxidative

phosphorylation(Electron Transportand Chemiosmosis)

Citricacidcycle

GlycolysisPyruvate

CO2

ATPCO2

ATP

NADH and FADH2

MitochondrionNADH

ATP

ATP (a) glucose andorganic fuels

has three stages

producesome

generates

Cellularrespiration

uses

H+ diffusethrough

ATP synthase

by process called

chemiosmosis

energy for

cellular work

uses

(b) (d)

(c)

(f)

(e)

oxidizes

C6H12O6

to pullelectrons down

to

uses pumps H+ to create

H+ gradient

producesmany

You should now be able to

1. Explain how photosynthesis and cellular respiration are necessary to provide energy that is required to sustain your life

2. Explain why breathing is necessary to support cellular respiration3. Describe how cellular respiration produces energy that can be stored

in ATP4. Explain why ATP is required for human activities5. Describe the process of energy production from movement of

electrons6. List and describe the three main stages of cellular respiration7. Describe the major steps of glycolysis and explain why glycolysis is

considered to be a metabolic pathway8. 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. Describe the citric acid cycle as a metabolic pathway designed for generating additional energy from glucose

10. Discuss the importance of oxidative phosphorylation in producing ATP

11. Describe useful applications of poisons that interrupt critical steps in cellular respiration

12. Review the steps in oxidation of a glucose molecule aerobically13. Compare respiration and fermentation14. Provide evidence that glycolysis evolved early in the history of life

on Earth15. Provide criteria that a molecule must possess to be considered a

fuel for cellular respiration16. 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, anelectron 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 (C3) and corn seedlings (C4) 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 C3 plants the advantage.

• As the plants photosynthesize the carbon dioxide levels will fall giving the C4 plants the advantage.

• The results are unpredictable.

C3 plant, low CO2 C4 plant, low CO2

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. G3P

ANSWER

H2O

ADPP

Lightreactions

Light

Chloroplast

NADPH

ATP

O2

Calvincycle

Sugar

CO2

NADP+ StromaThylakoidmembranes

Mitochondrionstructure

Intermembranespace

Membrane

Matrix

a.

H+

Chloroplaststructure

b.

c.

d.

e.

Photosynthesis

includes bothconverts

in which in which

(b) (c)

light-excitedelectrons ofchlorophyll

CO2 is fixed toRuBP

and then

(h)reduceNADP+ to

using

to produce

sugar(G3P)

(f)

chemiosmosis

(e)

(g)

by

producing

are passeddown

(d)

and

to

chemicalenergy

H2O is split

(a)

You should now be able to

1. Explain the value of autotrophs as producers2. Provide a general description of photosynthesis in chloroplasts3. Explain how plants are able to produce oxygen as a product of

photosynthesis4. Contrast photosynthesis to respiration in terms of redox reactions5. Describe the importance of visible radiation to photosynthesis6. Describe plant photosystems and their function in photosynthesis7. Describe the linkage (connection) between the two plant

photosystems8. Describe how chemiosmosis powers ATP synthesis in plants9. Discuss the Calvin cycle and how it uses ATP and NADPH10. Describe two plant adaptations that save water in hot, dry climates11. Detail how photosynthesis could help moderate globing warming12. Discuss the importance of the Earth’s protective ozone layer

Copyright © 2009 Pearson Education, Inc.