Molecular Genetics

Molecular Genetics Jan 96,34 Use the following information to answer the next two questions Some Inherited Traits in House Cats Dominant Trait Allele Recessive Trait Allele Pointed ears P Folded ears p Smooth hair S Curly hair s Polydactyly (more D Five digits on paws d Than 5 digits on Paws) Assume that all of the alleles shown above exhibit independent assortment A folded-eared female mated with a male of unknown phenotype. All six of their offspring had pointed ears. What were the most probable genotypes of pp and PP Pp and Pp pp and Pp pp and pp Jan 96, 7 Numerical Response 1. A curly-haired, five digited male was crossed with a female that was heterozygous for both hair type and the number of digits on the paws. What is the probability of this mating producing offspring that have curly hair and are heterozygous for the number of digits on the paws? (Record your answer as a value from 0 to 1, rounded to two significant digits, in the numerical-response section of the answer sheet.) Answer: _________ Jan 96,35 Use the following information to answer the next two questions In Drosophila, ebony body colour is caused by the recessive allele eb and grey body colour by the dominant allele eb+. Vestigial wings are produced by the recessive allele vg and long wings by the dominant allele vg+. When mated, a female with ebony body colour and vestigial wings produced the following offspring: 41 flies with ebony body and long wings 44 flies with grey body and long wings 39 flies with grey body and vestigial wings 46 flies with ebony body and vestigial wings What was the genotype of the male parent in this cross? eb+eb+ vg+vg+ eb+eb vg+vg+ eb+eb vg+vg eb+eb vgvg Jan 96,36 How many of the 44 offspring with grey bodies and long wings would be expected to be heterozygous for body colour? 44 33 22 11 Jan 96,37 Use the following information to answer the next two questions An anemic condition in humans called thalassemia results from decreased production of hemoglobin. Three genes control the condition: N (normal hemoglobin), Thal-1 (thelassemia 1), and Thal-2 ( thalassemia 2). Possible genotypes and phenotypes for the trait are shown below Genotype Phenotype NN No anemia N Thal-1 Mild anemia N Thal-2 Mild anemia Thal-2 Thal-2 Mild anemia Thal-2 Thal-1 Moderate anemia Thal-1 Thal-1 Fatal—embryo or fetus dies before birth Which statement is consistent with the information given? Thal-1and Thal-2 are codominant and N is dominant Thal-1 is dominant over both N and Thal-2 N is dominant over both Thal-1 and Thal-2 N, Thal-1 and Thal-2 are codominant Jan 96,38 If a male with the genotype N Thal-1 and a female with the genotype N Thal-2 have a child, the probability of that child having some degree of anemia ( either mild or moderate ) is 1.00 0.75 0.50 0.25 Jun 96,37 Use the following information to answer the next question When a gene that directs cells of the human anterior pituitary to synthesize HGH is transplanted into bacteria, it will cause the bacteria also to synthesize HGH. This HGH can be used to treat slowed skeletal growth in children. The phenomenon described illustrates that gene therapy can be used to cure inherited diseases in humans DNA is a universal language that can be read by all organisms bacteria, like humans, use insulin to regulate their sugar metabolism humans have acquired some bacterial genetical traits through symbiotic relationships Jun 96,38 Use the following information to answer the next question The sequence in which these events occur is 1,3,5,6,4,2 1,3,6,5,2,4 3,1,5,6,4,2 3,1,6,5,2,4 Jun 96,39 Use the following information to answer the next two questions. If structure 1, structure 3, and structure 8 were combined to form a molecule, it would be an amino acid a nucleic acid a uracil nucleotide an adenine nucleotide Jun 96,40 One likely result of a mutation could be the replication of the DNA segment transcription of the RNA segment replacement of structure 3 in the RNA segment with structure 2 replacement of structure 4 in the DNA segment with structure 7 Jun 96, 41 Use the following information to answer the next two questions The first codon in the mRNA strand is CAG GTC CUG GUC Jun 96,7 Use this additional information to answer the next question Numerical Response 2. The second codon in the DNA double helix is TAT. What is the amino acid coded by this triplet? (Record your answer in the numerical-response section of the answer sheet.) Answer: ____________ Jun 97,29 Use the following information to answer the next question The results illustrated can be best interpreted as showing that the genetic material was deoxyribonucleic acid some of the virulent bacteria had survived heat treatment genetic material from the dead virulent bacteria had entered the living avirulent bacteria genetic material from the avirulent strain caused the change to the virulent bacteria Jun 97,30 Use the following information to answer the next two questions The nitrogen bases for positions X and Y are, respectively uracil and guanine uracil and cytosine adenine and cytosine thymine and guanine Jun 97,31 The amino acid labeled W is methionine tryptophan arginine alanine Jun 97,32 Use the following information to answer the next two questions Which process would allow a mutation in the location shown to be passed on to the next generation? Mitosis Oogenesis Nondisjunction Spermatogenesis Jun 97,33 By causing physical damage to a cellular component, ionizing radiation or chemicals can cause mutations. The site of this damage is the nuclear membrane the protein structure of the ribosome one or more amino acids in a crucial enzyme one or more nucleotides in the DNA molecule Jun 97,34 Use the following information to answer the next question A bacterium has been found that synthesizes a type of plastic called polyhydroxybutyrate (PHB). Researchers can remove genes from this bacterium, “cut” open the DNA in plant cells, and insert the bacterial genes. Plants grown from these transformed cells will synthesize PHB. -from Science News The row that identifies the enzymes likely used by researchers to move the genes from the bacterium to a plant is Row Enzyme(s) Used on Bacterial DNA Enzymes(s) Used on Plant DNA A. Ligase only Ligase and restriction B. Restriction only Ligase only C. Restriction only Restriction and ligase D. Restriction and ligase Restriction only Jun 97,35 Use the following information to answer the next question Which structures in the diagrammed human cell contain DNA? Structures 1 and 3 Structures 1 and 4 Structures 2 and 3 Structures 3 and 5 Jun 98,37 Use the following information to answer the next question If structure 4 is adenine, then structure 8 is uracil adenine thymine cytosine Jun 98,38 Use the following information to answer the next question Which amino acid sequence would be found in a polypeptide that is produced using the coded information in the above DNA sense strand? Leucine – glycine – glutamate Phenylalanine – proline – glutamate Leucine – glcine – glutamate – tyrosine Asparagine – proline – valine – methionine Jun 98,39 Use the following information to answer the next question The technology to replace genes in cells of humans is called gene cloning gene therapy carrier screening DNA fingerprinting Jun 98,40 Use the following information to answer the next three questions If a DNA triplet is CTA, then the complementary DNA triplet is GAU GAT CUA CTA Jun 98,41 PCR is similar to process that normally occurs in cells prior to cell division. The row that identifies the site and name of this process is Row Site Process A. nucleus replication B. nucleus transcription C. cytoplasm replication D. cytoplasm transcription Jun 98,42 Which enzymes would a geneticist use to cut DNA into fragments? Ligase enzyme RNA polymerases DNA polymerases Restriction enzymes Jun 98,43 Use the following information to answer the next four questions The most likely explanation for the success following the transplant of healthy cells in mice is that the healthy cells produced antibodies that repair the damaged cells transferred FAH-producing genes to the damaged liver underwent meiosis more rapidly than the damaged cells produced enough FAH enzyme to restore the function of the liver Jun 98,44 Which of the following statements about cells is demonstrated by this research? Genes control cell division in liver cells Genes control the production of the FAH enzyme in cells Liver cells in an individual are genetically identical to each other Liver cells cannot regenerate themselves by the process of mitosis Jun 98,45 The presence of patches of healthy cells in the damaged human livers may indicate that enzymes are not normally coded for by genes in liver cells liver cells in an individual can undergo genetic change and cell division liver cells migrated into the damaged livers from other places in the body enzymes are produced in various places in the body and then migrate into the liver Jun 98,8 Numerical Response 3. The sequence of events that produces the enzyme FAH (a protein) in liver cells is __________. tRNA transports amino acids to the ribosome information from DNA is used to form mRNA mRNA carries the message to the ribosome ribosome encounters a terminator (stop) codon (Record your four-digit answer in the numerical-response section of the answer sheet.) Answer: _____ _____ _____ _____ Jan 00,34 Use the following information to answer the next question Which of the following effects would this mutation have on an individual’s body? A chronic increase in blood sugar after meals A chronic decrease in blood sugar after meals A decrease in the body’s metabolic rate after meals An increase in the body’s metabolic rate after meals Jan 00,35 Use the following information to answer the next question In this sample of Escherichia coli DNA, the percentage of the nitrogen base molecules that would be adenine is 76.4 % 38.2 % 23.6 % 11.8 % Jan 00,36 Use the following information to answer the next two questions Which of the following statements is a reasonable conclusion based on this information? The gene with the inserted DNA fragment is recessive The gene with the inserted DNA fragment is dominant The affected gene produces a protein that influences embryonic development The affected gene cannot be transcribed after foreign DNA has been inserted Jan 00,37 If two heterozygous mice were mated, what percentage of their offspring would be predicted to die? 0 % 25 % 50 % 75 % Jan 00,38 Use the following information to answer the next two questions The sequence of events that would enable researchers to incorporate the CTX gene into bacterial DNA would be to first open the bacterial DNA with ligase enzymes, then position the CTX gene in the DNA, and then join the DNA by restriction enzymes first open the bacterial DNA with restriction enzymes, then position the CTX gene in the DNA, and then join the DNA by ligase enzymes first position the CTX gene in the DNA, then open the DNA with the ligase enzymes, and then join the DNA by restriction enzymes first position the CTX gene in the DNA, then open the DNA with restriction enzymes, and then join the DNA by ligase enzymes Jan 00,39 The overall effects of cholera toxin are opposite to the physiological effects of which of the following hormones? Oxytocin Thyroxine Aldosterone Epinephrine Jan 00,40 Use the following information to answer the next two questions The most direct relationship between a gene and an enzyme is that an enzyme causes a gene to destroy carcinogens the sequence of nucleotides in a gene determines the structure of an enzyme each gene contains the code needed to construct many different types of enzymes the sequence of amino acids in an enzyme is unrelated to nucleotide sequence in a gene Jan 00,5 Use the following additional information to answer the next question Numerical Response 4. The sequence of events that results in the production of the cancer-fighting enzyme is _____, _____, _____, and _____. (Record your four-digit answer in the numerical-response section on the answer sheet.) Jan 01,35 Use the following information to answer the next three questions The normal function of the p53 gene is likely to encourage a cell to undergo mitosis encourage a cell to undergo meiosis prevent an abnormal cell from reproducing prevent the transcription of a cell suicide gene Jan 01,36 Use the following additional information to answer the next two questions The initial research findings described above demonstrate that the activated p53 gene causes cancer in lab animals demonstrate that the p53 protein causes the formation of cancer cells indicate that the normal p53 gene is responsible for preventing cancer in all mammals indicate that the normal p53 gene is responsible for preventing cancer under laboratory conditions Jan 01,37 Gene therapy that might stop in controlled cell division due to the mutant p53 allele would require one functional p53 allele to be successfully inserted into cancer cells two functional p53 alleles to be successfully inserted into cancer cells one functional p53 allele to be successfully removed from cancer cells two functional p53 alleles to be successfully removed from cancer cells Jan 01,38 Which of the following rows correctly describes a DNA molecule? Row Components Backbone Molecules that form the links between two strands A. amino acids, sugars, and bases sugars and bases amino acids B. amino acids, sugars, and bases sugars and amino acids bases C. phosphates, sugars, and bases sugars and bases phosphates D. phosphates, sugars, and bases sugars and phosphates bases Jan 01,39 Use the following information to answer the next question The proportions of three of the mRNA nucleotides produced from this DNA are 20% adenine, 30% uracil, and 10% cytosine 40% cytosine, 20% adenine, and 30% uracil 20% uracil, 40% cytosine, and 10% guanine 20% thymine, 30% adenine, and 10% guanine Jan 02,22 Use the following information to answer the next six questions Which of the following statements summarizes the effect of insulin and the effect of glucagon on blood glucose levels? Both insulin and glucagon tend to raise blood glucose levels. Both insulin and glucagon tend to lower blood glucose levels Insulin tends to raise blood glucose levels; whereas, glucagon tends to lower blood glucose levels Insulin tends to lower blood glucose levels; whereas, glucagon tends to raise blood glucose levels Jan 02,23 Use the following additional information to answer the next four questions A reasonable hypothesis to explain these results is that the mutation in the mitochondrial DNA that caused KSS in the man first occurred in the mother’s oocytes man’s somatic cells man’s spermatocytes mother’s somatic cells Jan 02,24 Both males and females can be affected by mitochondrial mutations, but only females can transmit genetic mutations to their offspring. For this inheritance pattern, which of the following rows gives the contributions to the zygote made by the sperm and by the egg? Row Sperm Contribution Egg Contribution A. nuclear contents only both nuclear and cytoplasmic contents B. both nuclear and cytoplasmic contents nuclear contents only C. neither nuclear nor cytoplasmic contents both nuclear and cytoplasmic contents D. both nuclear and cytoplasmic contents neither nuclear nor cytoplasmic contents Jan 02,25 Mitochondrial DNA and nuclear DNA both code for the formation of proteins. Which of the following statements about protein synthesis is true? A mRNA anticodon binds with an amino acid codon, which results in the placement of a specific tRNA molecule in the polypeptide chain. A mRNA anticodon binds with a tRNA codon, which results in the placement of a specific polypeptide molecule in the amino acid chain. A tRNA anticodon binds with an mRNA codon, which results in the placement of a specific amino acid molecule in the polypeptide chain. A tRNA anticodon binds with a polypeptide codon, which results in the placement of a specific mRNA molecule in the amino acid chain. Jan 02,26 Use the following additional information to answer the next question The third amino acid coded for by this segment of mitochondrial DNA is lysine threonine glutamate phenylalanine Jan 02,27 Use the following additional information to answer the next question In this study, the manipulated variable was the amount of mitochondrial DNA tested time of migration from one continent to another amount of variation in mitochondrial DNA base sequences geographic location of subjects whose sample of mitochondrial DNA was tested