Biology 196 Ex. 4 My Lab and Mastering

18.2-.3 HW-Copy Adaptive Follow-Up Practice Test 18.27 Part A Which of the following best describes the current understanding of the makeup of the human genome?

Genes for noncoding RNA make up the majority of meaningful genetic information in the human genome. Ex: Our growing understanding of the human genome is revealing that much of it is transcribed but not translated to form a large repertoire of small and large RNA molecules that play a vital role in gene regulation and likely in other processes that have not yet been discovered.

20HW Adaptive Follow-Up Chapter 8 Pre-Test Question 6 Part A Enzymes are described as catalysts, which means that they _____. See Concept 8.4 (Page 153)

increase the rate of a reaction without being consumed by the reaction Ex: This permits enzyme molecules to be used repeatedly.

18.1 HW Activity: The lac Operon in E. coli Part E Which of these is a regulatory gene?

D Ex: The regulatory gene is not a part of the operon.

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part G Part complete Which of the following has the greatest potential as a cancer treatment?

Find a way to turn off the gene for making telomerase in cancer cells, since the cells would stop dividing when the telomeres were gone.

18.1 HW Adaptive Follow-Up Chapter 4 Question 4 Part A Visualize the structural formula of each of the following hydrocarbons. Which hydrocarbon has a double bond in its carbon skeleton?

C2H4

20HW Adaptive Follow-Up Practice Test 16.02 Part A Avery and his colleagues' 1944 experiment showed that DNA __________.

was the substance that transformed the bacteria in Griffith's experiment Ex: Avery and his colleagues announced that the transforming agent was DNA.

18.1 HW Adaptive Follow-Up Chapter 5 Pre-Test Question 1 Part A A dehydration reaction (or condensation reaction) is the process in which _____. See Concept 5.1 (Page 67)

water molecules are produced as a polymer is formed from monomers Ex: Monomers are joined together in a reaction in which two molecules are covalently bonded to each other through the loss of a water molecule; this is called a condensation reaction or, specifically, a dehydration reaction.

18.1 HW Adaptive Follow-Up Practice Test 5.35 Part A Which of the following lists ranks these molecules in the correct order by size from smallest to largest?

water, glucose, sucrose, protein Ex: In this case, the ranking is from smallest to largest.

18.1 HW Activity: The lac Operon in E. coli Part C Regulatory proteins bind to _____.

the operator Ex: Transcription is inhibited when a regulatory protein binds to the lac operon operator

20HW Adaptive Follow-Up Activity: How Enzymes Work Part A In general, enzymes are what kinds of molecules?

proteins Ex: Enzymes are proteins.

20HW Adaptive Follow-Up Chemistry Review - Carbohydrates: Functions of Carbohydrates Part A Polymers that contain sugars ...

(a), (b), and (c). Ex: Good choice! Polymers that contain sugars do all the named functions and more. For example, they also lubricate the path of roots through soil and they glue plant cells together.

18.1 HW Adaptive Follow-Up Get Ready for this Chapter: Chapter 5 Question 1 In this chapter, you will learn about the structures and functions of the four classes of large biological molecules. Before beginning this chapter, you should be able to explain the bonding behavior of a carbon atom (see Concept 4.2, section entitled "The Formation of Bonds with Carbon"). The following question provides a quick check of your basic knowledge in this area. Part A How many hydrogen atoms can be attached to carbon B?

1 Ex: If you had trouble with this question, review the following material: Each carbon atom can form four bonds. A double bond counts as two bonds, so carbon B has a total of three bonds so far and it can form one more single bond with a hydrogen atom.

20HW Adaptive Follow-Up Practice Test 4.28 Part A What is ATP's importance in the cell?

ATP stores the potential to react with water, thereby removing a phosphate group and releasing energy for cellular processes. Ex: ATP releases energy during a hydrolysis reaction that removes a phosphate group.

13HW Video Tutor Session Quiz: Mitosis vs. Meiosis Part D 5 10 15 20 the answer cannot be determined

10 Ex: If the hypothetical organism has 5 chromosomes in one of its gametes, then it must have 10 chromosomes in a body cell. Just before mitosis, the chromosomes in a body cell are duplicated, but the sister chromatids remain joined together. So you will see 10 (duplicated) chromosomes in a typical body cell.

18.2-.3 HW-Copy Activity: Control of Transcription Part B Which of these indicates an enhancer region?

A Ex: This is an enhancer region.

18.1 HW Activity: The lac Operon Part G Which of the following enzymes converts ATP to cAMP?

Adenylyl cyclase Ex: Adenylyl cyclase converts ATP to cAMP, which helps CAP bind and facilitates binding of RNA polymerase to the lac promoter.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part D - Interpreting the graph Do the data suggest that any of these possible control elements are actual control elements?

All three appear to be control elements. Ex: All three elements appear to be control elements because when they were deleted, the levels of reporter mRNA differed from the level produced by the intact enhancer construct.

20HW Adaptive Follow-Up Practice Test 8.32 Part A Which of the following statements about enzymes is INCORRECT?

An enzyme is consumed during the reaction it catalyzes. Ex: If enzymes were consumed during the reaction they catalyzed, they would not be able to act as a catalyst. This statement is incorrect.

20HW Adaptive Follow-Up Misconception Question 39 Part A How does an enzyme increase the rate of the chemical reaction it catalyzes?

An enzyme reduces the free energy of activation (EA) of the reaction it catalyzes. Ex: An enzyme catalyzes a reaction by lowering EA, enabling the reactant molecules to absorb enough energy to reach the transition state even at moderate temperatures. Read about enzymes and activation energy.

18.1 HW Adaptive Follow-Up Get Ready for This Chapter: Chapter 5 Question 2 In this chapter, you will learn about the structures and functions of the four classes of large biological molecules. Before beginning this chapter, you should be able to identify the important biological functional groups (see Figure 4.9). The following question provides a quick check of your basic knowledge in this area. Part A Which functional group(s) shown below is (are) present in all amino acids?

B and C Ex: If you had trouble with this question, review the following material: An amino acid has an amino group (−NH2−NH2) and a carboxyl group (−COOH−COOH)

18.2-.3 HW-Copy Activity: Control of Transcription Part A _____ bind(s) to DNA enhancer regions.

Activators Ex: Activators are a type of transcription factor that bind to enhancer regions

18.1 HW Activity: The lac Operon Part A Which of the following statements best defines the term operon?

An operon is a region of DNA that codes for a series of functionally related genes under the control of the same promoter. Ex: This arrangement of genes is common in bacteria. For example, genes involved in lactose metabolism are clustered in the lac operon of E. coli, and genes involved in tryptophan metabolism are in the trp operon.

18.2-.3 HW-Copy Activity: Control of Transcription Part C Which of these directly bind(s) to the promoter?

C and D Ex: Both RNA polymerase and transcription factors bind with the promoter.

20HW Adaptive Follow-Up Chapter 16 Question 7 Part A A biochemist isolates, purifies, and combines in a test tube a variety of molecules needed for DNA replication. When she adds some DNA to the mixture, replication occurs, but each DNA molecule consists of a normal strand paired with numerous segments of DNA a few hundred nucleotides long. What has she probably left out of the mixture?

DNA ligase

20HW Visualizing the Concept: Enzymes are used to "cut and paste" DNA Part C Check each of the true statements about the proteins involved in cutting and pasting DNA. More than one statement may be true. Check all that apply.

DNA ligase pastes together segments of DNA with matching sticky ends. A restriction enzyme cuts DNA while DNA ligase pastes DNA. A particular restriction enzyme only cuts DNA at one very specific DNA sequence. Ex: The two enzymes involved are restriction enzymes (which cut DNA) and DNA ligase (which pastes DNA).

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part G Did deletion of any of the possible control elements cause an increase in reporter gene expression? How can you tell?

Deletion of control element #1 or #2 caused an increase in reporter gene expression; both constructs resulted in over 100% of the control level of mRNA. Ex: For cells incubated with the DNA constructs in which element #1 or #2 was deleted, the amount of reporter mRNA made was over 100% of the amount of reporter mRNA made by the cells in the control group. This result indicates that the deletion of control element #1 or #2 causes an increase in reporter gene expression.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part E Did deletion of any of the possible control elements cause a reduction in reporter gene expression? How can you tell?

Deletion of element #3 caused a reduction in reporter gene expression; that construct resulted in less than 50% of the control level of mRNA. Ex: For cells incubated with the DNA construct in which element #3 was deleted, the amount of reporter mRNA made was less than 50% of the amount of reporter mRNA made by the cells in the control group. This result indicates that the deletion of control element #3 causes a reduction in reporter gene expression.

20HW Adaptive Follow-Up Activity: Gel Electrophoresis of DNA Part A Which of these DNA molecules is the shortest?

E Ex: The shorter the DNA molecule, the farther it moves

20HW Visualizing the Concept: Enzymes are used to "cut and paste" DNA Part B Which one of the following statements is correct?

If a restriction enzyme is combined with a piece of DNA that contains its restriction site, the result will be restriction fragments. Ex: A restriction site on a piece of DNA contains the specific base sequence that is recognized by the restriction enzyme. Once the cut is made, the resulting smaller pieces are called restriction fragments.

18.1 HW Activity: The lac Operon Part C What is allosteric regulation?

In allosteric regulation, a small molecule binds to a large protein and causes it to change its shape and activity. Ex: Allosteric regulation is an important mechanism for changing enzyme activity, as well as for changing the function of some gene repressors and activators.

18.2-.3 HW-Copy Adaptive Follow-Up Chapter 16 Pre-Test Question 10 Part A Which of the following is true of DNA during interphase? See Concept 16.3

It exists as chromatin and is less condensed than mitotic chromosomes. Ex: Chromatin is the term for the loosely coiled DNA observed in cells during interphase. Even during interphase, however, parts of the chromosome may still be rather tightly coiled and packed.

18.1 HW Activity: The lac Operon in E. coli Part A The operon model of the regulation of gene expression in bacteria was proposed by _____.

Jacob and Monod Ex: In 1961 Jacob and Monod proposed the operon model of gene regulation.

13HW Video Tutor Session Quiz: Mitosis vs. Meiosis Part A mitosis meiosis gametogenesis both mitosis and meiosis none of the above

Mitosis Ex: Mitosis goes on continuously in most parts of the body, whereas meiosis takes place only in the gonads.

20HW Video Tutor Session Quiz: DNA Profiling Part B gel electrophoresis RFLP analysis DNA profiling DNA fingerprinting PCR

PCR Ex: This machine is a PCR machine. PCR is a method for amplifying DNA.

18.1 HW Activity: The lac Operon Part B What molecule binds to promoters in bacteria and transcribes the coding regions of the genes?

RNA polymerase Ex: RNA polymerase is the enzyme that binds to promoters and transcribes the coding regions of genes into RNA.

18.2-.3 HW-Copy Activity: Transcription Initiation in Eukaryotes Part E Which of the following events in transcription initiation likely occurs last?

RNA polymerase binds to the promoter of the gene. Ex: RNA polymerase is recruited only when other transcription factors, including TBP, are assembled at the promoter.

20HW Adaptive Follow-Up Practice Test 16.26 Part A Which of the following components is required for DNA replication?

RNA primer Ex: In the cell, the preexisting chain, the primer needed to initiate DNA elongation, is RNA, not DNA.

18.2-.3 HW-Copy Activity: Review: Control of Gene Expression Part C What is the function of a spliceosome?

RNA processing Ex: Spliceosomes are involved in RNA processing.

20HW Evaluating Science in the Media: Genetically Modified Organisms Part B - Authority How can you know if the person or organization providing the information has the credentials and knowledge to speak on this topic? One clue is the type of web site it is--the domain name ".org" tells you that this site is run by a nonprofit organization. Now scan the post to find the name and credentials of the person who wrote it. What is the affiliation of the writer?

She is on staff at the Center for Food Safety (CFS). Ex: The page indicates that Sharon Perrone is on staff at the Center for Food Safety. Can you find her credentials on the site? Another thing to look for is how recently the information on the site was posted or updated. A well maintained, authoritative web site should be updated or reviewed often.

20HW Adaptive Follow-Up Practice Test 16.29 Part A Once the DNA at the replication fork is unwound by helicases, what prevents the two strands from coming back together to re-form a double helix?

Single-strand binding proteins bind the unwound DNA and prevent the double helix from re-forming. Ex: As soon as the helicase passes, the single-strand binding proteins rapidly coat the unwound DNA and prevent the strands from coming back together.

18.2-.3 HW-Copy Adaptive Follow-Up Practice Test 18.25 Part A Which of the following best depicts coordinate control of genes in eukaryotes?

The second and third listed responses are correct. Ex:Coordinate control of genes involved in a specific cellular process but scattered over different chromosomes is facilitated by: 1) a specific combination of control elements and activator molecules being shared by every gene of a dispersed group and 2) the congregation of the dispersed genes on different chromosomes into transcription factories within the nucleus.

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part E Part complete Which cells are most likely to have the gene for making telomerase switched on

The cells in a developing embryo.

18.1 HW Adaptive Follow-Up Misconception Question 37 Part A What is the free energy change (ΔGΔG) of the hydrolysis of ATP to ADP?

The free-energy change (ΔGΔG) of the hydrolysis of ATP to ADP and Pi may vary considerably with variations in pH, temperature, atmospheric pressure, and concentrations of reactants and products. Ex: The free-energy change (ΔGΔG) of the hydrolysis of ATP to ADP and Pi is -7.3 kcal/mole under standard conditions. Standard conditions are defined as a temperature of 298 K (or 250C), 1 atm, pH 7, and equal 1M concentrations present of all reactants and products. In living cells, conditions do not conform to standard conditions, primarily because reactant and product concentrations differ from 1 M. For example, when ATP hydrolysis occurs under cellular conditions, the actual ΔGΔG is about -13 kcal/mol, 78% greater than the energy released by ATP hydrolysis under standard conditions.

20HW Adaptive Follow-Up Chapter 16 Pre-Test Question 1 Part A Griffith's experiments with S. pneumoniae were significant because they showed that traits could be transferred from one organism to another. What else did he find that was significant? See Concept 16.1 (Page 315)

The transferred traits were heritable. Ex: The fact that offspring of transformed bacteria also showed the pathogenic trait meant that the transforming agent had to be involved with the genetic material.

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part F Part complete Which of the following is NOT true about naked mole rats?

Their cells do not produce telomerase.

18.1 HW Activity: The lac Operon Part E What happens to the expression of the lacI gene if lactose is not available in the cell?

There is no change—the lacI gene is constitutively expressed Ex: The lacI gene is expressed regardless of the presence of lactose. Only the structural genes of the lac operon are affected by the presence or absence of lactose.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part H If deletion of a control element causes an increase in gene expression, what must be the normal role of that control element?

To repress gene expression; without the control element, repressors are not able to bind to the enhancer, and the level of gene expression increases.

14HW Scientific Skills Exercise: Making a Histogram and Analyzing a Distribution Pattern Part B In order to discern patterns in the distribution of alleles, it is helpful to sketch a curve over the bars of the histogram, and a line through the highest bar. (Figure 2) What pattern does the distribution of frequency values show in this histogram?

a normal distribution, characterized by frequencies that are symmetrically distributed around one central peak value Ex: The frequencies are symmetrically distributed around one central peak value. This is often called a "bell curve."

18.1 HW Adaptive Follow-Up Practice Test 5.44 Part A A glucose molecule is to starch as __________.

a nucleotide is to a nucleic acid Ex: Nucleotides are the monomers that make nucleic acid polymers, just as glucose is the monosaccharide (monomer) from which starch (polymer) is constructed.

13HW Meiosis (1 of 3): Genes, Chromosomes, and Sexual Reproduction (BioFlix tutorial) Part C - Animal life cycles In the life cycle of an organism, meiosis is paired with the process of fertilization. Understanding the life cycle of an organism is the key to understanding how sexual reproduction ensures the inheritance of traits from both parents and also introduces genetic variation. Complete the diagram to show the life cycle of a typical animal. Follow these steps: Drag labels of Group 1 to identify each stage of the life cycle. Drag labels of Group 2 to identify the ploidy level at each stage. Drag labels of Group 3 to identify the process by which each stage occurs. Labels can be used once, more than once, or not at all.

a. 2n b. 2n c.meiosis d. meiosis e. n f. egg g. sperm h. n i. fertilization j. 2n k. zygote l. mitosis m. 2n n. meiosis o. n p. egg

13HW Meiosis (2 of 3): The Mechanism (BioFlix tutorial) Part B - Crossing over Crossing over plays a critical role in increasing the genetic variation among offspring of sexual reproduction. It is important to understand how crossing over occurs and its consequences in meiosis. Look carefully at the diagrams depicting different stages in meiosis in a cell where 2n = 6. Assume that the red chromosomes are of maternal origin and the blue chromosomes are of paternal origin. Drag the labels to fill in the targets beneath each diagram of a cell. Note that the diagrams are in no particular order. Drag labels of Group 1 to identify the stage of meiosis depicted in each diagram. Drag labels of Group 2 to identify whether the configuration of the chromosomes related to crossing over is possible or not.

a. anaphase ii b. metaphase ii c. prophase i d. metaphase i e. yes f. no g. no h. yes Ex: Crossing over occurs during prophase I when homologous chromosomes loosely pair up along their lengths. Crossing over occurs only between nonsister chromatids within a homologous pair of chromosomes, not between the sister chromatids of a replicated chromosome. Only segments near the ends of the chromatids, not segments nearest the centromeres, can exchange DNA.

20HW Adaptive Follow-Up Learning through Art: Structures of a Prokaryotic Cell Can you label the structures of a prokaryotic cell? Part A Drag the labels to the appropriate locations in this diagram.

a. fimbriae b. nucleoid c. plasma membrane d. cell wall e. capsule f. flagella g. bacterial chromosome h. ribosomes

18.1 HW Adaptive Follow-Up Learning through Art: The lac Operon Can you correctly fill in the table that summarizes how the lac operon works in E. coli? Part A This figure shows the conditions under which the lac operon in E. coli is turned off and on.

a. off b. off c. on d. on e. on

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part C Many enzymes are named for the substrate on which they work, either to build or disassemble molecules. Also, enzyme names often end in "-ase." For example, lactase is the enzyme that breaks down lactose. With a name like "telomerase," we can deduce that telomerase is probably:

an enzyme that regulates the assembly of DNA at the ends of chromosomes

18.1 HW Adaptive Follow-Up Activity: Making and Breaking Polymers Part A What is another name for a condensation reaction?

dehydration Ex: Condensation, also called dehydration, refers to the removal of a water molecule during the linking of monomers.

20HW Adaptive Follow-Up Activity: How Enzymes Work Part F What is the correct label for "A"?

energy of activation Ex: The energy of activation must be overcome in order for a reaction to proceed.

20HW Adaptive Follow-Up Practice Test 16.01 Part A During Griffith's experiments with Streptococcus pneumoniae in mice, material from __________ bacteria transformed __________ bacteria.

heat-killed pathogenic ... living nonpathogenic Ex: Griffith found that some of the living nonpathogenic cells were converted to the pathogenic form.

20HW Adaptive Follow-Up Activity: How Enzymes Work Part C An enzyme _____.

is an organic catalyst Ex: Enzymes are proteins that behave as catalysts.

20HW Adaptive Follow-Up Chapter 20 Pre-Test Question 6 Part A Gel electrophoresis separates DNA fragments on the basis of what characteristic? See Concept 20.1

length Ex: As the DNA fragments move through the gel, longer fragments are impeded more than shorter fragments, producing characteristic banded patterns in the gel.

18.2-.3 HW-Copy Adaptive Follow-Up Practice Test 5.27 Part A The sex hormones estradiol and testosterone belong to which class of molecules?

lipids Ex: Steroids, such as estradiol and testosterone, are lipids based on their insolubility in water. The molecules are characterized by a carbon skeleton consisting of four fused rings of carbon atoms.

18.1 HW Activity: The lac Operon in E. coli Part D In the presence of a regulatory protein the lac operon is _____.

not transcribed Ex: The regulatory protein of the lac operon is a repressor.

20HW Video Tutor Session Quiz: DNA Profiling Part A polynucleotide phosphate base sugar double helix

phosphate Ex: The phosphate group of a nucleotide, represented here as a yellow ball, contains a negative charge

18.2-.3 HW-Copy Activity: Review: Control of Gene Expression Part A Enzyme complexes that break down protein are called _____.

proteasomes Ex: Proteasomes are enzyme complexes that break down proteins.

18.2-.3 HW-Copy Activity: Review: Control of Gene Expression Part D Protein-phosphorylating enzymes' role in the regulation of gene expression involves _____.

protein activation Ex: Proteins are often activated by phosphorylation.

20HW Adaptive Follow-Up Activity: How Enzymes Work Part B Part complete Enzymes work by _____.

reducing EA Ex: Enzymes work by reducing the energy of activation.

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part B What are telomeres?

regions of DNA at the end of chromosomes which do not code for making proteins

20HW Adaptive Follow-Up Activity: How Enzymes Work Part D What name is given to the reactants in an enzymatically catalyzed reaction?

substrate Ex:This is the name given to the reactants in an enzymatically catalyzed reaction.

18.1 HW Adaptive Follow-Up Practice Test 18.06 Part A In an inducible operon, the inducer is often the __________ in the pathway being regulated; the inducer binds to the __________, which then becomes __________.

substrate ... repressor ... inactive Ex: The presence of the substrate turns the operon on by binding to the repressor and inactivating it.

20HW Adaptive Follow-Up Practice Test 5.16 Part A In a 1-4 glycosidic linkage, __________.

the number 1 carbon in one monosaccharide is bound to the number 4 carbon in another monosaccharideone Ex: Glycosidic linkages, the covalent bonds that link simple sugars, are named according to the carbon atoms they join.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part B What was the dependent variable in this experiment?

the relative level of reporter gene mRNA Ex: The dependent variable was the relative level of reporter gene mRNA because that was the response that was measured in the experiment.

20HW Adaptive Follow-Up Learning through Art: DNA Profiling Drag the terms to their correct locations in this diagram.

1. DNA isolation 2. PCR 3. gel electrophoresis a. STR analysis b. long DNA fragment c. short DNA fragment

18.2-.3 HW-Copy Adaptive Follow-Up Building Vocabulary: Lipids Can you complete these sentences about lipids? Part A Drag the terms on the left to the appropriate blanks on the right to complete the sentences. Not all terms will be used.

1. Lipids are diverse compounds that are grouped together because they are hydrophobic. 2. A fat molecule is composed of two types of smaller molecules: glycerol and fatty acids. 3. A fatty acid consists of a carboxyl group and a long hydrocarbon chain. 4. Unsaturated fatty acids have one or more double bonds in their hydrocarbon chains and are usually found in vegetable oils. 5. The hydrocarbon chains of saturated fatty acids are not kinked, and thus pack closely together, making animal fats solid at room temperature. 6. Phospholipids are a major component of cell membranes. They form a bilayer with their hydrophobic tails mingling together and their hydrophilic heads facing the watery environment on both sides of the membrane. 7. Steroids are lipids with a structure consisting of four fused rings. Many sex hormones are made from this type of lipid.

20HW Evaluating Science in the Media: Genetically Modified Organisms Part F - Evaluation Finally, how can you use your assessment of the authority, motivation, and reliability of the information to evaluate this web site relative to other sources? Use the scales below to assign a numerical score to this source. Assign a numerical score for each category. Then add up the total score. (The highest possible score is 6; the lowest is 0.) In what range does this source fall?

2 to 4 Ex: This source is in the mid-range of trustworthiness. Some of the information may be good, but the overt bias and minimal primary source citation should lead you to seek out further information from other authoritative, unbiased sources. How does this score compare to the score you gave at the beginning of the activity?

20HW Video Tutor Session Quiz: DNA Profiling Part D Please use this figure to answer the question posed in the video: A B C D E

A Ex: This gel has one band near the top, which represents a long piece of DNA, and two bands near the bottom, which represent two short pieces of DNA.

18.2-.3 HW-Copy Activity: Transcription Initiation in Eukaryotes Part B Which of the following regulatory elements is not composed of DNA sequences?

Activators Ex: Activators are proteins that are involved in transcription initiation.

18.1 HW Adaptive Follow-Up Activity: Making and Breaking Polymers Part C Match the monomers with their polymers.

Carbohydrate polymers are made up of simple sugar monomers. Nucleic acid polymers are made up of nucleotide monomers. Protein polymers are made up of amino acid monomers.

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part D Part complete How is the aging process linked to telomeres?

Cells with short telomeres can no longer divide, so damaged tissues cannot be repaired.

18.2-.3 HW-Copy Adaptive Follow-Up Practice Test 5.28 Part A High cholesterol levels are considered a major risk factor for heart disease. If it is so bad for humans, why does the body make cholesterol in the first place?

Cholesterol is the precursor for many important molecules such as sex hormones. Ex: Cholesterol is the basis for many steroid molecules, including sex hormones.

13HW Meiosis (2 of 3): The Mechanism (BioFlix tutorial) Part C - Changes in ploidy and DNA content during meiosis The parent cell that enters meiosis is diploid, whereas the four daughter cells that result are haploid. Which statement correctly describes how cellular DNA content and ploidy levels change during meiosis I and meiosis II?

DNA content is halved in both meiosis I and meiosis II. Ploidy level changes from diploid to haploid in meiosis I, and remains haploid in meiosis II. Ex: During anaphase of both meiosis I and meiosis II, the DNA content (number of copies of chromosomes) in a cell is halved. However, the ploidy level changes only when the number of unique chromosome sets in the cell changes. This occurs only in meiosis I (where separation of homologous chromosomes decreases the ploidy level from 2n to n and produces daughter cells with a single chromosome set).

18.2-.3 HW-Copy Activity: Transcription Initiation in Eukaryotes Part D Which of the following regulatory DNA sequences might be located thousands of nucleotides away from the transcription start site of a gene?

Enhancer Ex: Enhancers can function thousands of nucleotides away from the promoter and transcription start site.

14HW Scientific Skills Exercise: Making a Histogram and Analyzing a Distribution Pattern Part C What is the best explanation for the curve's shape?

Equal numbers of light-skin and dark-skin alleles result in a majority of the offspring having intermediate phenotypes.

18.2-.3 HW-Copy Activity: Transcription Initiation in Eukaryotes Part C True or false? Regulatory and basal transcription factors regulate transcription by binding to the promoter.

False Ex: Basal transcription factors do indeed bind to the promoter, but regulatory transcription factors bind to promoter-proximal elements and enhancers.

18.2-.3 HW-Copy Activity: Transcription Initiation in Eukaryotes Part F True or false? One possible way to alter chromatin structure such that genes could be transcribed would be to make histone proteins more positively charged.

False Ex: The positive charge on histone proteins allows them to interact tightly with negatively charged DNA, thus inhibiting transcription. To disrupt this interaction, the histone proteins would have to be made more negatively charged.

18.1 HW Activity: The lac Operon Part H True or false? The mechanism by which glucose inhibits expression of the lac structural genes is known as catabolite stimulation, whereas the mechanism by which lactose stimulates expression of the lac structural genes is known as allosteric regulation.

False Ex: The process by which lactose binds to the lac repressor and inactivates it by causing it to change shape is known as allosteric regulation. However, the process by which glucose causes cAMP levels in the cell to drop, thereby preventing CAP from stimulating expression of the lac structural genes, is known as catabolite repression.

18.2-.3 HW-Copy Activity: Transcription Initiation in Eukaryotes Part A Which of the following terms describes the DNA-protein complexes that look like beads on a string?

Nucleosome Ex: The "beads on a string" appearance of nucleosomes comes from the wrapping of DNA around a core of eight histone proteins.

18.1 HW Activity: The lac Operon Part D Under which conditions are the lac structural genes expressed most efficiently?

No glucose, high lactose Ex: When glucose is absent and lactose levels are high, the lac structural genes are expressed the most efficiently. Without glucose, cAMP is produced and CAP can stimulate transcription of the structural genes. In the presence of lactose, the repressor does not bind to the operator and therefore does not block transcription.

18.2-.3 HW-Copy Adaptive Follow-Up Practice Test 11.10 Part A Steroid hormones can enter a cell by simple diffusion. Therefore, steroids do which of the following?

None of the listed responses is correct. Ex: Simple diffusion must occur down a gradient, and as the molecule moving must pass through the membrane, that molecule must be nonpolar; no membrane protein is required for passive diffusion.

20HW Adaptive Follow-Up Everyday Biology: Can Humans Live Forever? Part A Which of the following problems during DNA replication is being illustrated with the kids in the video?

Nucleotides at the ends of the DNA strands are lost when DNA replicates.

20HW Evaluating Science in the Media: Genetically Modified Organisms Part D - Reliability How can you know if the information is based on scientifically collected data and if it's corroborated by other sources? Look more closely around the web page. Click the "serious risks" link in the fourth paragraph; then click the "scientific review" link in the sixth paragraph. What do you find when you click these two links?

One links to another page on the CFS web site, and one links to a paper in a peer-reviewed journal. Ex: The "serious risks" link goes to another page on the CFS site. Would you feel more confident in the information there if scientific papers were cited?The "scientific review" link goes to a paper from a peer-reviewed journal. Think about whether the author of the blog post was being selective in what evidence she presented from the Annual Review of Phytopathology paper.

20HW Evaluating Science in the Media: Genetically Modified Organisms Part E Now, search for information on GMOs on at least two other web sites, including the United States Department of Agriculture (USDA.gov) and the World Health Organization (WHO.int). Is the information provided by these sites consistent with what you found on the CFS web site?

Other sites discuss both the risks and benefits associated with GMOs. Ex: When the information is consistent with several other sources, or is even cited by other sources, that's a good sign that the source you're evaluating is reliable. However, if there are substantial inconsistencies, you should avoid relying on any single source.

18.2-.3 HW-Copy Adaptive Follow-Up Learning through Art: Chromosome Packing Can you correctly label the structures in this diagram that summarizes chromosome packing? Part A Drag each label to its proper place in the diagram.

a. histone b. nucleosome c. supercoil d. chromosome e. chromatin

20HW Adaptive Follow-Up Practice Test 5.42 Part A Which type of protein shields a newly forming protein from cytoplasmic influences while it is folding into its functional form?

chaperonins Ex: Chaperonins shield proteins from "bad influences" (interactions with other molecules in the cytoplasm) while they are folding into their functional forms.

20HW Adaptive Follow-Up Misconception Question 99 Part A Cold case detectives are investigating a homicide that took place 30 years ago. In reexamining the evidence, they find a tiny spot of blood on the victim's clothing that was likely left by the murderer. The DNA in the blood has partially degraded over time. What technique(s) would the blood lab technicians use in their examination of this tiny, degraded blood sample? Select all that apply.

They would use PCR to amplify the DNA. Ex: PCR is impressive in the speed and specificity with which it amplifies DNA. Only minute amounts of DNA need be present in the starting material, and this DNA can be in a partially degraded state, as long as a few molecules contain the complete target sequence. Read about the polymerase chain reaction.

18.1 HW Activity: The lac Operon Part F What is the function of the lacZ gene?

This gene encodes an enzyme, b-galactosidase, which cleaves lactose into glucose and galactose. Ex: The lacZ gene encodes b-galactosidase, a key enzyme in lactose metabolism. When lactose is present in the cell, the cell expresses lacZ and metabolizes lactose.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part F If deletion of a control element causes a reduction in gene expression, what must be the normal role of that control element?

To activate gene expression; without the control element, activators are not able to bind to the enhancer, and the level of gene expression decreases.

20HW Adaptive Follow-Up Learning through Art: Building Maltose, a Double Sugar Can you label the sugar molecules, type of reaction, and atoms or molecules shown in the chemical reaction below? Part A This diagram shows a chemical reaction in which two glucose molecules combine to form a molecule of maltose. Drag the labels to their appropriate locations in the diagram. First, drag labels onto the targets in Group 1 to identify the types of sugars and the type of reaction shown. Then drag labels onto the targets in Group 2 to identify the atoms, chemical groups, or molecules involved. Not all labels will be used

a. monosccharide b. dehydration reaction c. disaccharide d. OH e. H f. H2O

13HW Meiosis (1 of 3): Genes, Chromosomes, and Sexual Reproduction (BioFlix tutorial) Part B - Interactions among chromosomes This diagram shows a diploid nucleus (2n=8) in which chromosome replication has occurred in preparation for mitosis (top) and meiosis (bottom). The nucleus at top right is now in prophase of mitosis; the nucleus at bottom right is now in prophase I of meiosis. Drag the labels to their appropriate targets to correctly identify the various chromosome structures. Labels can be used more than once.

a. non-homologous chromosomes b. sister chromatids c. homologous chromosomes d. centromere e. nonsister chromatids f. homologous chromosomes g. sister chromatids Ex: To understand the process of meiosis, it is essential that you can differentiate between sister chromatids, nonsister chromatids, homologous chromosomes, and non-homologous chromosomes.

13HW Meiosis (1 of 3): Genes, Chromosomes, and Sexual Reproduction (BioFlix tutorial) Part A - Meiosis terminologyPart complete Drag the labels from the left to their correct locations in the concept map on the right.

a.chromatin b.genes c. chromosomes d. genome e. traits f. locus g. gametes Ex: Knowing the terms and relationships shown in this concept map will help you understand the role that meiosis plays in heredity, sexual reproduction, and genetic variability.

13HW Meiosis (2 of 3): The Mechanism (BioFlix tutorial) Part A - The stages of meiosis Can you recognize the eight stages of meiosis based on the location and behavior of the chromosomes? Drag the diagrams of the stages of meiosis onto the targets so that the four stages of meiosis I and the four stages of meiosis II are in the proper sequence from left to right. (Note that only one of the two daughter cells is shown for meiosis II.)

a.double paired single bubble b. double paired lined up in middle c. double paired pulled away from middle d. paired double bubble e. single paired f. single paired lined up in middle g. single paired pulled away from middle h. single strand double bubble Ex: Meiosis involves two sequential cellular divisions. In meiosis I, homologous chromosomes pair and then separate. Thus, although the parent cell is diploid (containing two chromosome sets, one maternal and one paternal), each of the two daughter cells is haploid (containing only a single chromosome set). In meiosis II, the sister chromatids separate. The four daughter cells that result are haploid.

18.1 HW Adaptive Follow-Up Practice Test 18.07 Part A You have inserted the gene for human growth factor into the E. coli lactose operon, replacing the structural genes with the gene for human growth factor. What substance must you add to your culture of bacteria to cause them to produce human growth factor for you?

allolactose Ex. Allolactose will bind to the repressor protein, inactivating it, and allowing transcription of the genes in the operon, including human growth factor.

13HW Video Tutor Session Quiz: Mitosis vs. Meiosis Part C centrosome chromosome telomere centromere tetrad

centromere Ex: The centromere is the point of attachment between two sister chromatids of a duplicated chromosome.

18.2-.3 HW-Copy Adaptive Follow-Up Practice Test 18.12 Part A In eukaryotes, DNA packing seems to affect gene expression primarily by __________.

controlling access to DNA Ex: For example, the genes of tightly packed heterochromatin are usually not transcribed, presumably because RNA polymerase and other necessary proteins can't make contact with the DNA.

20HW Adaptive Follow-Up Practice Test 20.04 Part A Bacteria use restriction enzymes to __________.

destroy foreign DNA Ex: Restriction enzymes are used to protect bacteria against intruding DNA from other organisms.

20HW Adaptive Follow-Up Practice Test 16.25 Part A After the formation of a replication bubble, which of the following is the correct sequence of enzymes used for the synthesis of the lagging DNA strand?

helicase, primase, DNA polymerase, ligase Ex: First the double helix is unwound; primase makes the RNA primer; DNA polymerases elongate the growing strand and replace the RNA primer with DNA; and DNA ligase joins the Okazaki fragments.

18.1 HW Adaptive Follow-Up Activity: Making and Breaking Polymers Part B What is the name of the process during which a bond between two monomers is broken?

hydrolysis Ex: Hydrolysis is the opposite of a condensation reaction. During hydrolysis, a water molecule is used up in the breaking of a bond between two monomers. An H is added to one monomer, and an OH is added to the other.

20HW Adaptive Follow-Up Activity: How Enzymes Work Part E As a result of its involvement in a reaction, an enzyme _____.

is unchanged Ex: Enzymes are not changed as a result of their participation in a reaction.

20HW Adaptive Follow-Up Get Ready for This Chapter: Chapter 16 Question 2 In this chapter, you will learn about the experiments that identified DNA as the genetic material, the structure of DNA and how it was discovered, how DNA is replicated, and how it is arranged in a chromosome and in the nucleus. Before beginning this chapter, you should be able to describe how enzymes carry out reactions (see Concept 8.4 and Figure 8.16). The following question provides a quick check of your basic knowledge in this area. Part A As a result of its involvement in a chemical reaction, an enzyme

is unchanged by the reactants or products. Ex: If you had trouble with this question, review the following material: An enzyme is a macromolecule that acts as a catalyst, a chemical agent that speeds up a reaction without being consumed or changed by the reaction. An enzyme catalyzes a reaction by lowering the EA barrier, enabling the reactant molecules to absorb enough energy to reach the transition state. Enzymes emerge from the reaction in their original form, having neither donated nor received matter or energy from the reactants.

13HW Video Tutor Session Quiz: Mitosis vs. Meiosis Part B mitosis only meiosis I only meiosis II only either mitosis or meiosis I either meiosis I or meiosis II

meiosis I only Ex: Meiosis I is the only time that chromosomes line up by homologous pairs.

20HW Adaptive Follow-Up Activity: Gel Electrophoresis of DNA Part B In gel electrophoresis DNA molecules migrate from _____ to _____ ends of the gel.

negative ... positive Ex: An electrical current is generated across the gel, and DNA molecules migrate from the negative end toward the positive end.

18.2-.3 HW-Copy Activity: Review: Control of Gene Expression Part B The nuclear membrane's role in the regulation of gene expression involves _____.

regulating the transport of mRNA to the cytoplasm Ex: This is the role of the nuclear membrane in the regulation of gene expression.

18.1 HW Activity: The lac Operon in E. coli Part B Which of these is NOT a component of the lac operon?

regulatory gene only Ex: The regulatory gene, while not a part of the operon, plays a role in regulating the expression of the genes of the operon.

20 HW Visualizing the Concept: Enzymes are used to "cut and paste" DNA Part A To create a molecule of recombinant DNA, which of the following is cut with a restriction enzyme? Check all that apply.

target DNA starting DNA Ex: To create a molecule of recombinant DNA, both the target DNA (shown in red in the figure) and the starting DNA (blue) are cut with the same restriction enzyme. This allows the sticky ends to hydrogen bond into the final recombinant DNA molecule.

20HW Video Tutor Session Quiz: DNA Profiling Part C the DNA will move down the gel but twice as fast the DNA will move in a circle it will move down the gel as normal nothing the DNA will move up the gel

the DNA will move up the gel Ex: DNA normally moves down through a gel due to the attraction of opposite charges. In this case, the DNA would move up the gel, toward the positive pole at the top.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part C What was the control treatment in this experiment?

the construct that had no DNA deleted from the enhancer Ex: The control treatment was the construct that had no DNA deleted from the enhancer. All the other treatment groups were compared to that control group.

14HW Scientific Skills Exercise: Making a Histogram and Analyzing a Distribution Pattern Part A - Interpreting a histogram If we assume that each square in the Punnett square represents one offspring of the heterozygous AaBbCc parents, then the squares below the Punnett square show the phenotypic frequencies of individuals with the same number of dark-skin alleles. These frequencies can then be plotted in a histogram. (Figure 1) Which phenotype has the highest frequency?

the phenotype that results from having 3 dark-skin alleles Ex: Individuals with 3 dark-skin alleles make up 20 out of 64 offspring, represented by the tallest bar in the histogram.

18.2-.3 HW-Copy Scientific Skills Exercise: Analyzing DNA Deletion Experiments Part A - Understanding the experimental design The diagrams show the intact DNA sequence (top) and the three experimental DNA sequences. A red X indicates the possible control element (1, 2, or 3) that was deleted in each experimental DNA sequence. The area between the slashes represents the approximately 8 kilobases of DNA located between the promoter and the enhancer region. The horizontal bar graph shows the amount of reporter gene mRNA that was present in each cell culture after 48 hours relative to the amount that was in the culture containing the intact enhancer region (top bar = 100%). What was the independent variable in this experiment?

the possible control element that was deleted Ex: The independent variable was the possible control element that was deleted from the experimental sequences because the researchers manipulated that variable in each treatment.

20HW Video Tutor Session Quiz: DNA Profiling Part E the profile from suspect 1 matches the crime scene the profile from suspect 2 matches the crime scene the profiles from suspects 1 and 2 both match the crime scene neither profile matches the crime scene you cannot conclude anything

the profile from suspect 2 matches the crime scene Ex: Notice that the locations of the bands in the right column, which is suspect 2, match the locations of bands in the first column from the crime scene. But the bands in the middle column do not match. Thus, we can conclude that the DNA profile from the crime scene matches the DNA profile from suspect 2.

20HW Adaptive Follow-Up Practice Test 16.03 Part A A scientist assembles a bacteriophage with the protein coat of phage T2 and the DNA of phage T4. If this composite phage were allowed to infect a bacterium, the phages produced in the host cell would have __________.

the protein and DNA of T4 Ex: The protein and DNA would match that of the phage whose DNA was used.

13HW Video Tutor Session Quiz: Mitosis vs. Meiosis Part E the start of meiosis I the start of mitosis just after meiosis I just before mitosis the start of meiosis II

the start of meiosis I Ex: We can see that the chromosomes are duplicated and lined up by homologous pair. That only happens at the start of meiosis I.

20HW Adaptive Follow-Up Practice Test 20.21 Part A In the polymerase chain reaction (PCR) technique, a heating phase and a cooling phase alternate. An original sample of DNA would have to pass through how many total rounds of heating and cooling before a sample is increased eight times in quantity?

three Ex: The amount of DNA doubles with each round. After one round, there is twice as much as was originally present. After two rounds, four times as much. After three rounds, eight times as much would be present.

20HW Evaluating Science in the Media: Genetically Modified Organisms Part C - Motivation Next, can you identify what the source is trying to accomplish by providing this information? As you read the post, think about what the writer's agenda might be with regard to GMOs. What seems to be the main purpose of the blog post?

to convince the public that genetic engineering is not the solution to citrus greening Ex: The Center for Food Safety opposes the use of GMOs. Think about how the organization's agenda might bias the information they present.