RNA Test 74 Questions with Verified Answers,100% CORRECT

RNA Test 74 Questions with Verified Answers RNA contains the sugar a. ribose. b. deoxyribose. c. glucose. d. lactose. - CORRECT ANSWER a Unlike DNA, RNA contains a. adenine. b. uracil. c. phosphate groups. d. thymine. - CORRECT ANSWER b Which of the following are found in both DNA and RNA? a. ribose, phosphate groups, and adenine b. deoxyribose, phosphate groups, and guanine c. phosphate groups, guanine, and cytosine d. phosphate groups, guanine, and thymine - CORRECT ANSWER c Which nucleotide in Figure 13-1 indicates the nucleic acid above is RNA? a. uracil b. guanine c. cytosine d. adenine - CORRECT ANSWER a Which of the following is true? a. RNA is usually single-stranded. b. DNA is usually single-stranded. c. DNA contains uracil. d. RNA contains thymine. - CORRECT ANSWER a Which type of RNA brings the information in the genetic code from the nucleus to other parts of the cell? a. rRNA b. tRNA c. mRNA d. RNA polymerase - CORRECT ANSWER c Which of the following is true of transcription? a. In eukaryotes, transcription takes place in the cytoplasm and requires many enzymes. b. RNA polymerase recognizes and binds to specific regions of the DNA called introns. c. RNA editing removes the exons from pre-mRNA, leaving only the introns in the final molecule. d. RNA polymerase can make many molecules of RNA from a single DNA sequence. - CORRECT ANSWER d Which of the following statements is true of eukaryotic DNA? a. A promoter is part of an intron. b. An intron is part of a promoter. c. Introns are sequences of DNA. d. Exons are edited out of pre-mRNA. - CORRECT ANSWER c Which molecules are involved in protein synthesis? a. transfer RNA, introns, and mutagens b. messenger RNA, introns, and ribosomal RNA c. ribosomal RNA, transfer RNA, and mutagens d. messenger RNA, ribosomal RNA, and transfer RNA - CORRECT ANSWER d From which molecules are mRNA molecules transcribed? a. tRNA b. rRNA c. DNA d. proteins - CORRECT ANSWER c What is produced during transcription? a. RNA molecules b. DNA molecules c. RNA polymerase d. proteins - CORRECT ANSWER a During eukaryotic transcription, an RNA molecule is formed that is a. complementary to both strands of DNA. b. identical to an entire single strand of DNA. c. double-stranded and inside the nucleus. d. complementary to part of one strand of DNA - CORRECT ANSWER d A promoter is a a. binding site for DNA polymerase. b. binding site for RNA polymerase. c. start signal for replication. d. stop signal for transcription. - CORRECT ANSWER b The three types of RNA are messenger RNA, transfer RNA, and *ribosomal* RNA. - CORRECT ANSWER True DNA molecules stay in the nucleus; RNA molecules leave the nucleus and move through the cytoplasm to the *ribosomes.* - CORRECT ANSWER True During *DNA replication,* only one strand of DNA serves as a template. - CORRECT ANSWER False, RNA transcription In Figure 13-6, A, B, and C are three types of ____________________. - CORRECT ANSWER RNA In RNA, _______________ is the sugar in the nucleotide. - CORRECT ANSWER ribose A eukaryotic gene consists of regulatory regions, a(an) ____________________, and the nucleotide sequence that is transcribed. - CORRECT ANSWER promoter During transcription, _________________________ binds to DNA and assembles nucleotides into a strand that is complementary to the DNA template. - CORRECT ANSWER RNA polymerase What is molecule B in Figure 13-6, and what is its function? - CORRECT ANSWER Molecule B is tRNA, which carries amino acids to the ribosomes. What are the three main parts of an RNA nucleotide? - CORRECT ANSWER A ribose molecule, a phosphate group, and a nitrogenous base are the three main parts of an RNAnucleotide. What might be the effect of a mutation in the promoter sequence of a gene? - CORRECT ANSWER RNA polymerase might be unable to bind to the promoter, and, as a result, the gene would not be transcribed. What must happen to a DNA molecule before RNA polymerase can begin to assemble nucleotides into a new RNA strand? - CORRECT ANSWER The DNA molecule must be separated into two strands. What does Figure 13-2 show? a. anticodons b. exons c. introns d. the genetic code - CORRECT ANSWER d How many nucleotides are needed to specify three amino acids? a. 3 b. 6 c. 9 d. 12 - CORRECT ANSWER c There are 64 codons and 20 amino acids. Which of the following is true? a. Several different codons can specify the same amino acid. b. Each codon specifies a different amino acid. c. Some amino acids have no link to a codon. d. Each amino acid is specified by only one codon. - CORRECT ANSWER a In Figure 13-3, which amino acid is specified by the mRNA code CCC? a. Gly b. Lys c. Ala d. Pro - CORRECT ANSWER d According to Figure 13-3, which code specifies the same amino acid as UAU? a. UAC b. UAA c. UGC d. UGU - CORRECT ANSWER a What happens during translation? a. Messenger RNA is made from a DNA code. b. The cell uses a messenger RNA code to make proteins. c. Transfer RNA is made from a messenger RNA code. d. Copies of DNA molecules are made. - CORRECT ANSWER b Which of the following terms is LEAST closely related to the others? a. spindle fiber b. tRNA c. polypeptide d. anticodon - CORRECT ANSWER a During translation, the type of amino acid that is added to the growing polypeptide depends on the a. codon on the mRNA and the anticodon on the rRNA. b. anticodon on the mRNA and the anticodon on the tRNA. c. anticodon on the rRNA and the codon on the mRNA. d. codon on the mRNA and the anticodon on the tRNA. - CORRECT ANSWER d A protein is being assembled when a. DNA is being translated. b. RNA is being transcribed. c. RNA is being translated. d. DNA is being transcribed. - CORRECT ANSWER c Genes contain instructions for assembling a. operons. b. nucleosomes. c. proteins. d. mutagens. - CORRECT ANSWER c Which is the correct sequence of the transfer of information in most organisms? a. protein to DNA to RNA b. RNA to DNA to protein c. DNA to RNA to protein d. RNA to protein to DNA - CORRECT ANSWER c What is an exception to the central dogma of molecular biology? a. Viruses sometimes transfer information from RNA to DNA. b. Viruses sometimes transfer information from DNA to RNA. c. Viruses sometimes transfer information from proteins to DNA. d. Viruses can translate without RNA. - CORRECT ANSWER a Which of the following best describes the what happens during gene expression? a. A cell reads the instructions in DNA and builds a protein based on those instructions. b. A gene is copied many times so that all of a cell's daughter cells will have their own copy. c. The nucleus of a cell builds cellular proteins based on the sequence of the mRNA code. d. A single gene leaves the nucleus of a cell and travels through the cytoplasm to the membrane. - CORRECT ANSWER a In eukaryotes a a. Transcription takes place in the cytoplasm, and translation takes place in the nucleus. b. Transcription takes place in the nucleus, and translation takes place in the cytoplasm. c. Transcription and translation both take place in the nucleus. d. Transcription and translation both take place in the cytoplasm. - CORRECT ANSWER b DNA contains the code for the *DNA polymerase* enzyme. - CORRECT ANSWER True A codon consists of *four* nucleotides. - CORRECT ANSWER False, three According to the chart in Figure 13-3, the codes GGA and GGU both code for *Ala.* - CORRECT ANSWER False, Gly The anticodon AGA is complementary to the mRNA codon *TCT.* - CORRECT ANSWER Flase, UCU Genes determine a person's eye color by coding for *introns* that affect eye color. - CORRECT ANSWER False, proteins The order of nitrogenous bases in DNA determines the order of ____________________ in proteins. - CORRECT ANSWER amino acids The codon that signals the end of a growing polypeptide is called a(an) __________________. - CORRECT ANSWER stop codon The tRNA bases called the ____________________ are complementary to three consecutive nucleotides on an mRNA molecule. - CORRECT ANSWER anticodons Two cellular processes, _____________ and _____________, are the main activities described in the central dogma of molecular biology. - CORRECT ANSWER transcription, translation According to Figure 13-2, what codons specify the amino acid glycine? - CORRECT ANSWER GGU, GGC, GGA, and GGG specify glycine. How many amino acids could be specified if codons consisted of two nucleotides instead of three? What problem would this present for an organism making proteins using all 20 amino acids? - CORRECT ANSWER There could be 16 combinations of nucleotides, which is too few combinations for all 20 amino acid to have a unique code. Within a cell, where does translation take place? - CORRECT ANSWER Translation takes place on ribosomes in the cytoplasm. Describe the functions of the three kinds of RNA illustrated in Figure 13-8. - CORRECT ANSWER Messenger RNA provides the code for the translation, ribosomal RNA reads the code, and a tRNA molecule brings the next amino acid specified by the code. What is the central dogma of molecular biology? - CORRECT ANSWER Information is transferred from DNA to RNA to protein. Explain the process of translation. - CORRECT ANSWER After a molecule of mRNA is transcribed in the nucleus it moves to the cytoplasm. A ribosome then positions itself at the start codon on the mRNA molecule. As each successive codon passes the ribosome, a molecule of tRNA brings an amino acid to the ribosome. Only a tRNA molecule with an anticodon that is complementary to the codon on the mRNA can attach an amino acid to the growing polypeptide chain. The ribosome attaches each new amino acid to the chain, and the bond holding the tRNA to the amino acid is broken. The ribosome moves to the next codon, and the process repeats until the entire mRNA molecule is translated. A mutation that involves one or a few nucleotides is called a. a mutagen. b. an inversion. c. a point mutation. d. a translocation. - CORRECT ANSWER c Which of the following is a chromosomal mutation? a. inversion b. insertion c. point mutation d. substitution - CORRECT ANSWER a One difference between a gene mutation and a chromosomal mutation is that a. A gene mutation affects the DNA of more genes than a chromosomal mutation. b. A gene mutation can involve a insertion or deletion, but cannot result in a frameshift. c. A chromosomal mutation can change the number of chromosomes in a cell. d. A chromosomal mutation is more likely to be passed on to offspring or daughter cells. - CORRECT ANSWER c When a chromosome undergoes a deletion mutation, information is a. repeated. b. lost. c. reversed. d. transferred. - CORRECT ANSWER b Most mutations a. have no effect on an organism. b. are fatal to an organism. c. are helpful to an organism. d. are harmful to an organism. - CORRECT ANSWER a What are some characteristics of polyploidy plants? a. They tend to be weaker and smaller than diploid plants. b. They tend to be bigger and stronger than diploid plants. c. They tend to be weaker, but bigger than diploid plants. d. They tend to be smaller, but stronger than diploid plants. - CORRECT ANSWER b A *deletion* mutation is shown in line B of Figure 13-5. - CORRECT ANSWER False, duplication A translocation mutation is seen in line *D* of Figure 13-5. - CORRECT ANSWER True Suppose that part of an amino acid sequence of a protein changed from tyrosine-proline- glycine-alanine to tyrosine-histidine- glycine-alanine. This change was most likely caused by a point mutation called a(an) ____________________. - CORRECT ANSWER substitution Insertions and deletions that change the entire genetic message that comes after the mutation are called ____________________. - CORRECT ANSWER frameshift mutations Mutant 1 in Figure 13-7 is the result of a(n) ________________ because part of the chromosome reverses direction. - CORRECT ANSWER inversion The element bromine can cause a genetic change, so bromine is called a ___________________. - CORRECT ANSWER mutagen What is a polyploid organism? - CORRECT ANSWER A polyploid organism is one that has many sets of chromosomes. What is one beneficial mutation that has happened in humans? - CORRECT ANSWER Sample answer: Mutations in humans have resulted in stronger bones and better disease resistance. What would happen to structure F in Figure 13-9 if structure C were deleted? - CORRECT ANSWER The base sequence of the codon (structure F) would change from GCU to GUG. In Figure 13-9, what effect would the deletion of structure C have on the process that occurs during step Y? - CORRECT ANSWER The deletion of structure C would shift the reading frame of the codons during translation. As a result, the sequence of the amino acids that follows after structure C might change. What term describes the general type of mutation occurring in A, B, C, and D in Figure 13-5? - CORRECT ANSWER A chromosomal mutation results from processes A, B, C, and D. Visuals In Figure 13-5, which process or processes involve two chromosomes? - CORRECT ANSWER Process D involves two chromosomes. Contrast process A and process B in Figure 13-5. - CORRECT ANSWER Process A results in the deletion of a segment of a chromosome. Process B results in the duplication of a segment of a chromosome. During which process in Figure 13-5 does a segment of a chromosome become oriented in the reverse direction? - CORRECT ANSWER A segment of a chromosome becomes oriented in the reverse direction during process C. In Figure 13-5, which process is a translocation? - CORRECT ANSWER Process D is a translocation.