Biology 207 Midterm II Exam

• Biology 207 Midterm II exam consists of 12 pages in total
• There are two parts to this exam, Part A with 28 multiple choice and Part B with 2 written answer questions
• Part A's answers should be written down on the General Purpose Answer Sheet and Part B's answers in the booklet provided
• You have 50 minutes to complete the exam

Question 1

• The consensus promoter sequence for the crit gene is TTACTA, located at the -5 position

Question 2

• A complete loss of function mutation for a repressor of a gene that promotes muscle growth, resulting in substantially increased muscle mass, is an example of a Hypermorph mutation

Question 3

• Monica used linear DNA samples, performed digestions with restriction enzymes, and used electrophoresis
• Determine the lanes with unmutated DNA digested with EcoRI, and DNA with 2000bp inserted between the Fsel and the right most EcoRI site followed by EcoRI digestion from gel electrophoresis results

Question 4

• Mendel knew each F1 generation contained two alleles because both parental phenotypes reappeared in the F2 generation

Question 5

• Genes that are constitutively expressed are controlled by state-dependent expression of regulatory genes is a FALSE statement

Question 6

• During transcription, the template strand of DNA is used to create RNA

Question 7

• Some bacterial genes are terminated via Rho-dependent termination
• Terminator sequences in DNA stall RNA Polymerase is a FALSE statement about this mechanism

Question 8

• Gain-of-function mutations include: a mutant gene product with a new function and a mutant gene expressed in a different tissue or cell

Question 9

• Pea plants were ideal for Mendel because they have characteristics for which the phenotypes are easy to differentiate

Question 10

• Mendel's "factors" (R and r) are now known as different alleles of the seed shape gene

Question 11

• Restriction enzymes EcoRI recognizes 5'-GAATTC-3' and HindIII recognizes 5'-AAGCTT-3
• Determine which sequences would NOT be cleaved by either enzyme

Question 12

• DNA ligase is not required for PCR

Question 13

• For a repressible operon, transcription normally takes place, and it is turned off by a(n) repressor

Question 14

• An individual with phenotype T (tall) is crossed with a test-crossed individual
• Half of the offspring have phenotype T and half have phenotype t - The genotypes of the individuals crossed were Tt and tt

Question 15

• All transposons share the step of making staggered breaks in the target DNA

Question 16

• Regulatory genes interact with other nucleotide sequences to affect transcription or translation

Question 17

• RNA and DNA have different properties
• RNA contains Hydrogen (H) at the 2' carbon of sugar instead of hydroxyl (OH) found in DNA is a FALSE statement

Question 18

• In DNA gel electrophoresis, larger DNA fragments will migrate farther than smaller DNA fragments is NOT true

Question 19

• An insertion sequence (IS) element, is a transposon between 700bp and 2500 bp long encoding only transposon activity proteins

Question 20

• The correct temporal sequence for bacterial transcription initiation is: iv > iii > ii > i: Promoter binding, Formation of transcriptional bubble, Addition of first rNTPs, Escape of transcriptional apparatus from promoter
• If the Sigma protein was not present, Promoter binding (iv) would be disrupted

Question 21

• The proper sequence of steps in PCR is: 4 > 1 > 3 > 2: Set temp to 90-100°C, Set temp to 30-60°C, Set temp to 72°C, Repeat (cycle)
• Step 1 (Set temp to 30-60°C) allows annealing of primers

Question 22

• A difference between PCR and DNA sequencing is that dideoxyribonucleosides are used only in DNA sequencing

Question 23

• E. A CRISPR array contains multiple spacers that are independently transcribed into multiple pre-crRNA transcripts. is not true about the CRISPR-Cas system

Question 24

• An organism with genotype Rr and phenotype R shows the concept of dominance

Question 25

• Mutation of DNA Polymerase II disrupting its binding to DNA would not disrupt basal transcription of a protein coding gene in Eukaryotes

Question 26

• Blue colonies indicate the plasmid does not have the D1R1 gene, colorless colonies indicate a successful D1R1 gene insertion
• An LB agar plate with ampicillin and X-Gal is the correct plate to use and collect colorless colonies, to obtain plasmids with successfully inserted D1R1 gene

Question 27

• Mendel's Principle of Segregation and Principle of Independent Assortment reflect different aspects of how genetic material propagates into gametes during Meiosis
• Principle of Independent Assortment occurs because different chromosomes (e.g., Chromosome 1 and 3) separate independently

Question 28

• Ribozymes are single stranded RNA molecules that can serve multiple functions including catalyzing reactions

Question 29

• Lac operon studies on E. coli mutants

Question 30

• Genetics of fruit fly body color and antennae length, including crosses of Ccaa males with cCAa females