Modern Biology Study Guide 49 - eaisbio

1 49 Modern Biology Study GuideName Class Date 50 Section 10-1 ReviewName Class Date 51 Copyright by Holt, Rinehart and Winston. All rights Biology Study GuideSECTION 10-2 REVIEWDNA STRUCTUREVOCABULARY REVIEWD efine the following terms and provide one example for base pair base MULTIPLE CHOICEW rite the correct letter in the primary function of DNA in cells is as a storage form for unused space in the nucleus to keep the nucleus from information that tells the cells which proteins to as a template for making long, spiral two strands of a DNA molecule are held together to the base-pairing rules, guanine binds of the following is NOT a correct structure of a nucleotide?

2 Deoxyribose deoxyribose ribose deoxyribose percentage of adenine in DNA to the percentage of to the percentage of related to the percentage of to the percentage of Class Date Copyright by Holt, Rinehart and Winston. All rights ANSWERA nswer the questions in the space are the three parts of a DNA nucleotide, and how are they connected to each other? 15% of the nucleotides in a DNA molecule contain guanine, what percentage of the nucleotidescontain each of the other three bases?

3 Explain your reasoning. is complementary base pairing important in DNA structure? ThinkingHow did X-ray diffraction photographs help Watson and Crick determine thestructure of DNA?STRUCTURES AND FUNCTIONSL abel each part of the figure in the spaces diagram below shows two nucleotide base pairs in a segment of a DNA 10-2 ReviewName Class Date CTabcd53 Copyright by Holt, Rinehart and Winston. All rights Biology Study GuideDNA REPLICATIONVOCABULARY REVIEWD efine the following fork replication MULTIPLE CHOICEW rite the correct letter in the replication can take place, polymerases must add complementary nucleotides to the two strands of DNA must covalent bonds in DNA must must break the bonds in the of the two DNA strands takes two different the same direction of the replication a direction opposite to that of the replication right angles to the direction of the replication replication in prokaryotes.

4 Are two replication forks move in opposite proceeds in one are no replication mutation is in the direction of a replication of of DNA in the nucleotide sequence of of the following enzymes is involved with breaking hydrogen bonds? aand bName Class Date SECTION 10-4 REVIEWC opyright by Holt, Rinehart and Winston. All rights ANSWERA nswer the questions in the space does replication occur so quickly in eukaryotes?

5 Is it important that exact copies of DNA are produced during replication? is DNA replication related to cancer? ThinkingWhy is it advantageous to have weak hydrogen bonds between complementarybases and strong covalent bonds between phosphate and deoxyribose groups in a DNA molecule? STRUCTURES AND FUNCTIONSThe figure below shows DNA replicating. In the spaceprovided, describe what is occurring at each lettered section of the 10-4 REVIEW54 Section 10-3 ReviewName Class Date Part REVIEWD efine the following MULTIPLE CHOICEW rite the correct letter in the protein is a polymer consisting of a specific sequence genetic code specifies the correlation DNA-nucleotide sequence and an RNA-nucleotide mRNA-nucleotide sequence and a tRNA-nucleotide

6 MRNA-nucleotide sequence and an rRNA-nucleotide RNA-nucleotide sequence and an amino-acid translation, one end of a tRNA molecule pairs with a sequence in eukaryotic cells, RNA is copied from DNA in amino acids are linked by a peptide bond ribosomes attach simultaneously to the same mRNA tRNAs pair with neighboring codons on an mRNA codons on an mRNA transcript bind to each ribosome attaches to two codons on an mRNA Class Date SECTION 10-3 REVIEWSHORT ANSWERA nswer the questions in the space , in order.

7 The tRNA anticodons that are complementary to the mRNA sequence AUGCAUGCAAGUUAG. How many amino acids will be in the polypeptide that is initially formed when this mRNA sequence is translated? why methionine is the first amino acid in every growing polypeptide. three ways that RNA differs from DNA. ThinkingHow would a deletion of one nucleotide in the middle of an mRNA transcriptaffect the polypeptide specified by that transcript? STRUCTURES AND FUNCTIONSL abel each part of the figure in the spaces diagram below summarizes the events that occur during Class Date aebfcgdh8 Copyright by Holt, Rinehart and Winston.

8 All rights Biology Study Guide Answer KeySection 10-2 VOCABULARY purine is a nitrogenous base with two rings ofcarbon and nitrogen atoms. Examples may includeadenine or pyrimidine is a nitrogenous base with one ringof carbon and nitrogen atoms. Examples mayinclude cytosine or complementary base-pair is a pair of nitrogenousbases connected to each other by hydrogenbonds. Examples may include adenine-thymineand nitrogenous base is a base in DNA containingnitrogen and three parts are a deoxyribose sugar, a phos-phate group, and a nitrogenous base. The phosphategroup and the base are connected to different partsof the guanine and cytosine are complementary,another 15% of the nucleotides must containcytosine.

9 The remaining 70% of the nucleotides(100% 30%) must contain adenine and thymine inequal proportions (35% each), since they are com-plementary to each base pairing is important becausethe hydrogen bonds between the bases hold thetwo strands of DNA together and because it servesas a way for DNA to X-ray diffraction photographs showed that theshape of the DNA molecule was a double AND FUNCTIONSa, deoxyribose; b, guanine; c, adenine; d, phosphate groupSection 10-3 VOCABULARY replication fork is a Y-shaped region that resultswhen the two strands of DNA separate helicase is an enzyme that separates the strandsof DNA during replication produces a newDNA molecule with one original strand and onenew occurs simultaneously at many originsalong the exact copies ensures that when a celldivides, the offspring cells will receive the samegenetic information as the parent can result when errors occur in the replica-tion of DNA in genes that control how a celldivides.

10 A mass of cancerous cells called a tumorcan hydrogen bonds break easily, making it easierfor the two strands in the molecule to separateduring replication. The strong covalent bondsensure that the sequence of nucleotides remainsfixed in each AND FUNCTIONSPart a: helicase enzymes separate DNA strands; Part b: DNA polymerase enzymes add complementarynucleotides to each original strand of DNA and cova-lent bonds form between adjacent nucleotides;Part c: DNA polymerases finish replicating DNA andfall off, two DNA molecules identical to original DNAmolecule have 10-4 VOCABULARY codon is a sequence of three mRNA nucleotidesthat codes for a specific amino acid or a start orstop is the process of assembling polypep-tides from information encoded in anticodon is a sequence of three tRNAnucleotides that pairs with a specific anticodons are UAC, GUA, CGU, and UCA.