Ch 13 Practice Test 93 Questions with Verified Answers,100% CORRECT, Exams of Nursing

Download Ch 13 Practice Test 93 Questions with Verified Answers,100% CORRECT and more Exams Nursing in PDF only on Docsity! Ch 13 Practice Test 93 Questions with Verified Answers The sequence of nitrogen-containing bases on one strand of DNA most directly determines the sequence of - CORRECT ANSWER amino acids in a protein molecule The sequence of nitrogen-containing bases on one strand of DNA could determine all of the following EXCEPT the sequence of A) nitrogen-containing bases in the other DNA strand. B) nitrogen-containing bases in mRNA. C) amino acids in a protein molecule. D) ribose and phosphate molecules in tRNA. - CORRECT ANSWER D) ribose and phosphate molecules in tRNA The "one-gene, one-enzyme" hypothesis concluded that - CORRECT ANSWER each allele codes for a single type of protein Which of the following is noted when comparing DNA and RNA? A) Adenine pairs with different bases in DNA and RNA. B) No sugar is present in either molecule. C) Hydrogen bonding is important only in DNA. D) Thymine pairs with different bases in DNA and RNA. E) Only DNA has a backbone made up of sugars and phosphates. - CORRECT ANSWER A) Adenine pairs with different bases in DNA and RNA. Which of the following is found in RNA but NOT in DNA? A) Deoxyribose B) Thymine C) Uracil D) Phosphate groups E) Adenine - CORRECT ANSWER C) Uracil Both DNA and RNA - CORRECT ANSWER contain phosphate groups How many consecutive mRNA bases are needed to specify an amino acid? - CORRECT ANSWER 3 What is the total number of different possible combinations of bases in a codon? - CORRECT ANSWER 64 If a bacterial protein is made from 30 amino acids, how many nucleotides are needed to code for its production? - CORRECT ANSWER 90 The genetic material of some viruses, such as HIV, is not DNA but is instead - CORRECT ANSWER RNA Which of the following molecules function to transfer genetic information from one generation to the next? A) tRNA B) Protein molecules C) Lipid molecules D) mRNA E) DNA - CORRECT ANSWER E) DNA If the sequence of bases in a section of DNA is TAGGCTAA, what is the corresponding sequence of bases in mRNA? - CORRECT ANSWER AUCCGAUU How many bases are in a codon? - CORRECT ANSWER 3 Which of the following has the fewest nucleotides in its strand? A) mRNA, having 50 codons B) Protein, having 40 amino acids C) mRNA, having 100 bases D) mRNA, having 75 nucleotides E) Protein, with 2 polypeptides, each having 35 amino acids - CORRECT ANSWER D) mRNA, having 75 nucleotides D) RNA chains of different genes can be transcribed from either DNA strand, with RNA polymerase traveling from the 3' end and moving toward the 5' end. - CORRECT ANSWER D) RNA chains of different genes can be transcribed from either DNA strand, with RNA polymerase traveling from the 3' end and moving toward the 5' end. In eukaryotes, a promoter that signals the beginning of the gene and binds with the promoter typically consists of - CORRECT ANSWER the bases TATAAA and response elements Which of the following occurs in the nucleus? A) Translation only B) Transcription only C) Replication of genetic material only D) Both transcription and replication of genetic material E) Both translation and replication of genetic material - CORRECT ANSWER D) Both transcription and replication of genetic material The process of converting the "message" of mRNA into a sequence of amino acids is called - CORRECT ANSWER translation What is the site of protein synthesis in the cell? - CORRECT ANSWER Ribosome All of the following are directly involved in translation EXCEPT A) amino acids. B) DNA. C) ribosomes. D) tRNA. E) mRNA. - CORRECT ANSWER B) DNA Suppose one strand of a "mini-gene" has the base sequence TACCCGGATTCA. If we assume no introns are involved, how many amino acids does the polypeptide encoded by this gene have? - CORRECT ANSWER 4 The manufacture of proteins from RNA and amino acids is referred to as - CORRECT ANSWER translation Suppose the template DNA strand of a "mini-gene" has the base sequence TACCCGGATTCA. The anticodon of the tRNA that carries the first amino acid to the ribosome will be - CORRECT ANSWER UAC A sequence of three RNA bases can function as a(n) - CORRECT ANSWER codon or anticodon In a wild-type strain of fruit flies, the length of a gene from the start to the stop codon is 2,000 DNA bases. Suppose an experiment indicated that the mRNA molecule transcribed from this gene is much shorter (only 1,200 bases). What is the most likely explanation for this? - CORRECT ANSWER There are introns in the DNA that were cut out of the mRNA. What molecule is responsible for translation of the four-letter "nucleic acid language" (A, T, G, and C nucleotides) into the 20 "amino acid language" of proteins by bringing in amino acids to the ribosome? - CORRECT ANSWER Transfer RNA A tRNA that carries a specific amino acid enters the protein-synthesizing machinery at the ribosomes and pairs with the appropriate - CORRECT ANSWER codon A tRNA molecule brings ________ to the ribosome during protein synthesis. - CORRECT ANSWER an amino acid Which of the following attaches to specific amino acids? A) Ribosomal RNA B) Messenger RNA C) RNA polymerase D) DNA E) Transfer RNA - CORRECT ANSWER E) Transfer RNA Which of the following has anticodons? A) RNA polymerase B) Transfer RNA C) Ribosomal RNA D) DNA E) Messenger RNA - CORRECT ANSWER B) Transfer RNA Which of the following is a protein made up of amino acids? A) Transfer RNA B) DNA C) Uracil D) Messenger RNA E) RNA polymerase - CORRECT ANSWER E) RNA polymerase Which of the following binds to codons? A) RNA polymerase B) DNA C) Transfer RNA D) Messenger RNA - CORRECT ANSWER C) Transfer RNA Which of the following contains codons? A) Transfer RNA B) Ribosomal RNA C) DNA D) Messenger RNA E) RNA polymerase - CORRECT ANSWER D) Messenger RNA Which of the following synthesizes RNA molecules in the nucleus? A) Transfer RNA B) Ribosomal RNA C) Messenger RNA D) RNA polymerase E) DNA - CORRECT ANSWER D) RNA polymerase Messenger RNA is single-stranded. - CORRECT ANSWER True In general, each gene codes for a specific protein. - CORRECT ANSWER True A codon of mRNA consists of three bases that code for an amino acid. - CORRECT ANSWER True The site of protein synthesis in the cytoplasm is the ribosome. - CORRECT ANSWER True Each ribosome is specific for a particular type of protein. - CORRECT ANSWER False tRNA is necessary for transcription to occur. - CORRECT ANSWER False Steroid hormones have the ability to regulate transcription. - CORRECT ANSWER True The Barr body is the X chromosome in the cell that is expressed, whereas the other X chromosome is inactivated. - CORRECT ANSWER False The strand of the DNA molecule that is transcribed is called the ________ strand. - CORRECT ANSWER template In eukaryotic cells, ________ occurs in the nucleus, resulting in the production of mRNA, which then travels to the ribosome for ________ into an amino acid chain. - CORRECT ANSWER transcription; translation The anticodon for the codon AUC is ________. - CORRECT ANSWER UAG A random change in the DNA nucleotide base sequence is called a ________. - CORRECT ANSWER Mutation A mutation in which one nucleotide in the DNA sequence is substituted for another nucleotide is referred to as a ________ mutation. - CORRECT ANSWER Point In females, an entire X chromosome is inactivated in each cell. The inactivated X chromosome is called the ________. - CORRECT ANSWER Barr Body In the intestinal bacteria Escherichia coli, the DNA segment that contains the coding for the enzymes of lactose metabolism is called the lactose ________. - CORRECT ANSWER operon List three ways in which an RNA molecule differs from a DNA molecule. - CORRECT ANSWER RNA is normally single-stranded, whereas DNA is double-stranded. RNA has the sugar ribose, whereas DNA has deoxyribose. RNA uses the base uracil, whereas DNA uses thymine. Determine the sequence of bases in mRNA if the original DNA base sequence is TAGGCTAA. - CORRECT ANSWER AUCCGAUU Describe the three basic steps or processes involved in transcription. - CORRECT ANSWER First, initiation involves RNA polymerase binding to a specific promoter region on the template strand of the DNA molecule. Second, elongation involves RNA polymerase moving along the DNA template strand and adding the appropriate complementary RNA nucleotides. Third, termination occurs when the RNA polymerase reaches a termination signal on the DNA template strand, and the new mRNA is released to move onto the cytoplasm. Compare and contrast the three major RNA molecules involved in translation. - CORRECT ANSWER mRNA, tRNA, and rRNA are all single-stranded RNA molecules transcribed from DNA that play distinct roles in the translation process. mRNA carries information from the DNA molecule for the sequence of amino acids for the polypeptide. tRNA carries the amino acids that correspond to specific codon units (on the mRNA via its anticodon). rRNA molecules are important subunits of the ribosome, which is the site of translation. Based on this table, which polypeptide would be synthesized from the mRNA base sequence AUGCCUGACUUA? - CORRECT ANSWER met-pro-asp-leu As seen in this figure, how many exons were used to assemble the pre-mRNA sequence, and how many exons were used in the finished mRNA? - CORRECT ANSWER 3; 3 In the fungus Neurospora, a metabolic pathway synthesizes the amino acid Z (which is essential for its survival) from the precursor W. The intermediates X and Y are also produced in this pathway. The enzymes E1, E2, and E3 catalyze three reactions in the process, as follows: E1 E2 E3 W→ X → Y → Z X-ray radiation can be used to create a mutant strain of Neurospora that has a defective gene sequence for E2.Based on this scenario, the mutant strain will survive on media that contain - CORRECT ANSWER only Y or Z Imagine that the short DNA base sequence GGCTGC is transcribed and then translated by a ribosome. The following activated tRNA molecules are available in the cytoplasm: tRNA Anticodon Amino Acid GGC proline CGU alanine UGC threonine CCG glycine ACG cysteine CGG alanine What resulting dipeptide will form? - CORRECT ANSWER Proline-threonine