Study Guides (238,092)
Canada (114,915)
Biology (1,397)
Tom Haffie (259)

2014 Term Test 2

12 Pages
Unlock Document

Western University
Biology 1001A
Tom Haffie

March 2014 Biology 1002B Page 1 of 12 Circle the best single letter choice for each of the following questions before transferring your answers to your computer sheet. Note: Questions may have 3, 4 or 5 choices. 1. Like all eukaryotes, the protozoan Giardia has undergone lateral gene transfer as shown by the presence of the gene cpn60 in its nuclear genome. What does cpn60 do in Giardia? A. It has no known function. B. It codes for an essential transcription factor. C. It codes for a component of the electron transport chain. D. It codes for a molecular chaperone that aids in th e folding of mitochondrial proteins. 2. Which of the following statements is thought to be the underlying reason for why a typical eukaryotic cell is more complex than a typical aerobic bacterial cell? A. A eukaryotic cell has a greater plasma membr ane area / cell volume ratio than a bacterium. B. A eukaryotic cell has a greater number of electron transport chains than a bacterium. C. An aerobic bacterium lacks membranes required for electron transport. D. An aerobic bacterium cannot undergo oxidati ve phosphorylation. 3. Bacteria and eukaryotes differ with respect to genome size. Which of the following statements about the trends seen in genome size is correct? A. The genome size of most bacteria is similar to eukaryotes. B. Within any specific group (e.g. flowering plants, mammals), genome size can differ by more than ten fold between organisms. C. Genome size seems to be related to complexity with mammals having the largest genomes. D. In general, organisms that are photosynthetic have smaller genome sizes than non - photosynthetic organisms. 4. Comparative studies of relative genome size can provide clues to evolutionary history. Which of the following lists correctly arranges the respective genomes in order of decreasing size? (Note: There is no need to know the actual genome sizes, just general trends.) A. Human Human Chlamydomonas Chlamydomonas nuclear mitochondrial nuclear mitochondrial B. Drosophila E. coli Vaucheria Vaucheria nuclear nuclear mitochondrial C. Human E. coli Chlamydomonas chloroplast genome and nuclear mitochondrial genome about the same size . D. Elysia E. coli Vaucheria Human nuclear chloroplast mitochondrial Code 222 Code 222 Code 222 March 2014 Biology 1002B Page 2 of 12 5. The petite mutation of the yeast Saccharomyces results in cells unable to generate ATP by oxidative phosphorylation. Which of the following is a possible genetic basis for this mutation? A. Defect to a mitochondrial gene that gets translated on cytosolic ribosomes. B. Defect to a mitochondrial gene that codes for nuclear protein. C. Defect to a nuclear gene that codes for a cytosolic protein. D. Defect to a nuclear gene that codes for a mitochondrial protein. 6. The image at the right shows a Southern blot (DNA probe hybridized to DNA) for the cox2 gene. DNA was isolated from the mitochondria (mtDNA) and nucleus (nDNA) of three different species (A, B, C). Based on your understanding of both lateral gene transfer and the image provided, which of the following statements is correct? 1. Lateral gene transfer has occurred in species C but not in species B. 2. As a result of lateral gene transfer, the protein -coding sequence of cox2 will be different in the mtDNA as compared to the nDNA of species A. 3. That no hybridization is detecte d in lane 2 may be because the probe is not similar enough to the cox2 gene in species B. 4. For species A, one would expect no hybridization with mtDNA at some point in the future. A. 1,2 and 3 B. 1 and 3 C. 2 and 4 D. 4 only E. All of 1,2,3 and 4 are correct 7. There are a number of different hypotheses proposed to explain why lateral gene transfer from mitochondria to the nucleus would be advantageous to eukaryotes. Which of the following statements lends support to the reactive oxyge n species (ROS) hypothesis of lateral gene transfer? A. The mitochondria of all species examined still maintain a genome. B. The genes that remain in the mitochondrial genome code for very hydrophobic proteins. C. Compared to a bacterial genome, the mutation rate of a eukaryotic nuclear genome is lower. D. All genes that encode a component of electron transport have undergone lateral gene transfer. Code 111 Code 111 Code 111 March 2014 Biology 1002B Page 3 of 12 8. The bacterium Rhizobium radiobacter is well known to biologists because it has the rather astonishing ability to cause natural genetic engine ering. That is, several genes are moved from the bacterial cells directly into the nucleus of cells of many higher plant species. Expression of these transferred genes in the infected plants stimulates c ell division, creating a mass of undifferentiated tissue. Which of the following signals on these transferred genes could be recognized in the plant host cell but not in the original Rhizobium cell? 1. “TATA” box 2. transcription terminator hairpin loop 3. intron splice signals 4. SD box A. 1, 2 & 3 B. 1 & 3 C. 2 & 4 D. 4 only E. All of 1, 2, 3 & 4 are correct 9. Which of the following is NOT an example of post -translational regulation? A. Acetylation of histones. B. Activation of CED – 3 caspase. C. Removal of signal tag upon crossing chloroplast membrane. D. Methylation of cytosine -phosphate-guanine (CpG) sequences. 10. Recall that tRNAs complementary base pair extensively with themselves in order to a achieve their functional shape. Think for a moment about what the underlying DNA sequence must be that promotes this self-pairing in RNA. The diagram below shows the DNA sequence of the template strand of a tRNA gene. The two boxed sequences result in RNA regions that base pair with each other following transcription to make a hairpin loop . (“N” just means “any nucleotide”.) Which of the following DNA sequences is appropriate for the empty box? A. TTCGTAATGGCCCGTA B. TACGGGCCATTACGAA C. ATGCCCGGTAATGCTT D. AAGCATTACCGGGCAT Code 111 Code 111 Code 111 March 2014 Biology 1002B Page 4 of 12 11. Cauliflower mosaic virus is an important pathogen of some agricultural crops. A particular section of the viral genome has been found to increase ex pression of any protein -coding gene as shown below. Location of Viral Sequence Amount of gene expression No viral sequence (Control) ++ Sequence is far upstream of gene ++ Sequence is immediately upstream of gene ++++++ Sequence is in first intron of gene ++ Sequence is immediately downstream of gene ++ Given the above gene expression data, what type of sequence is this? A. start codon B. SD box C. promoter D. enhancer 12. Since it has been so extensively studied, the lac operon regulation system is frequently used in genetic engineering to drive expression of other genes. This is often done using a technique called “gene fusion” in which the coding region of the gene of in terest is “pasted” onto the first part of the coding region of the galactosidease gene ( LacZ) as shown beloAfter translation, the small galactosidease fragment can be removed. Assume that you try to get rich by expressing the gene for human growth hormone in E. coli using a LacZ fusion. You are happy to see a protein produced but sad to discover that it isn’t growth hormone. What is a likely cause of this problem? A. E. coli might be using a different genetic code and puttindifferent amino acids. B. When fusing the coding regions, you might not have matched the reading frame of the hormone gene with that of the LacZ gene. C. Maybe you fused the growth hormone gene in backwards. The normal template strand is being transcribed 5’ to 3’. D. E. coli is using different signals to splice out introns. Code 111 Code 111 Code 111 March 2014 Biology 1002B Page 5 of 12 13. The diagram at right shows the result of alternative splicing of a given precursor mRNA in two different plant tissues: leaf and seed. Consider a single base pair insertion mutation near the middle of the DNA sequence that gives rise to the mRNA region labeled exon 4. Which of the following descriptions of the consequence of this mutation is accurate? A. The insertion will make the mature mRNA longer in seed. B. The impact of this insert ion depends on which protein this is. C. The insertion will alter the reading frame in leaf but not in seed. D. The insertion will disrupt splicing and result in defective proteins in leaf and seed. 14. The DNA sequence of the lac operon enables E. coli metabolism to regulate the production of enzymes needed to use lactose in the environment as a carbon and energy source. If you discover a mutant strain of E. coli that cannot grow when lactose is in the environment, where might the mutation be? 1. lacZ coding region; loss of function 2. lacY coding region; loss of function 3. lac promoter; loss of function 4. lacI coding region; loss of allolactose binding function A. 1, 2 & 3 B. 1 & 3 C. 2 & 4 D. 4 only E. All of 1, 2, 3 & 4 are correct 15. Consider this sequence from the template strand of the CED - 9 gene of C. elegans. 3’ ATG GGC AAA GTT CGC CAT TAG With reference to the genetic code at right (shown as mRNA codons), which of the following CED – 9 gene sequences contains a silent mutation? A. ATG GGC AAA GTG CAT TAG B. ATG GGC AAA GGT CAT TAG C. ATG GGC AAA GTC CAT TAG D. ATG GGC AAA GTT CAT TAG Code 111 Code 111 Code 111 March 2014 Biology 1002B Page 6 of 12 16. Which of the following types of RNA could participate in complementary base pairing with mRNA during normal gene express ion/regulation in Denis Maxwell? 1. tRNA 2. miRNA (microRNA) 3. snRNA 4. rRNA A. 1, 2 & 3 B. 1 & 3 C. 2 & 4 D. 4 only E. All of 1, 2, 3 & 4 are correct 17. The diagram at right is a screen shot from the simulation used in class showing a small amount of available lactose and various components of the lac operon. Which o
More Less

Related notes for Biology 1001A

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.