Docsity
Log inSign up
Docsity
Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity

Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan

Guidelines and tips
Guidelines and tips
Sell on Docsity
Sell on Docsity
Log inSign up

Prepare for your exams

Study with the several resources on Docsity

Find documents

Prepare for your exams with the study notes shared by other students like you on Docsity

Search Store documents

The best documents sold by students who completed their studies

Search through all study resources
Docsity AINEW

Summarize your documents, ask them questions, convert them into quizzes and concept maps

Explore questions

Clear up your doubts by reading the answers to questions asked by your fellow students

Earn points to download

Earn points by helping other students or get them with a premium plan

Share documents
download point icon20 Points

For each uploaded document

Answer questions
download point icon5 Points

For each given answer (max 1 per day)

All the ways to get free points
Get points immediately

Choose a premium plan with all the points you need

Study Opportunities

Choose your next study program

Get in touch with the best universities in the world. Search through thousands of universities and official partners

Community

Ask the community

Ask the community for help and clear up your study doubts

University Rankings

Discover the best universities in your country according to Docsity users

Free resources

Our save-the-student-ebooks!

Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors

From our blog

Exams and Study
Go to the blog

Exam 2 with Practice Problems - Molecular Biology | MICR 302, Exams of Molecular biology

Southern Illinois University (SIU) - CarbondaleMolecular biology

Material Type: Exam; Class: Molecular Biology; Subject: Microbiology; University: Southern Illinois University Carbondale; Term: Spring 2003;

Typology: Exams

2009/2010

Uploaded on 02/24/2010

koofers-user-o1q
koofers-user-o1q 🇺🇸

5

(1)

10 documents

1 / 8

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Name SS#
MICR 302: Introduction to Molecular Biology
Exam II Spring, 2003
Multiple Choice Questions (2 points each)
Circle the letter next to the single best answer
1. Mutations are hereditary only if:
a) they occur in germ cells
b) they occur in coding sequences cells
c) they occur in mitochondrial DNA
d) they affect the process of transcription
e) they affect the process of replication
2. The difference between a true revertant and a second site revertant is as follows:
a) A true revertant has the original DNA sequence restored
b) A true revertant has an altered protein, but this works as well as the original
version
c) A second site revertant had two original mutations, both of which have reverted
d) A second site revertant results from an insertion followed by a deletion (or vice
versa) so that the overall length of the DNA is unchanged
e) A second site revertant relies on having a gene duplication to replace the
defective copy
3. When DNA is repaired by the mismatch repair system:
a) The parental strand is recognized because it still contains uracil from the RNA
primer
b) The parental strand is recognized because its GATC sequences are methylated
c) The new strand is recognized because its cytosine residues are methylated
d) Restriction enzymes cut out regions of the double helix that are distorted
e) RNA Polymerase fills in the gaps first with temporary RNA
4. A conservative substitution is a base substitution that results in:
a) an exon being substituted with an intron during a splicing event
b) a codon coding for an amino acid being substituted with a stop codon
c) one amino acid being replaced with another amino acid with similar chemical
properties
d) one amino acid being replaced with another amino acid with very different
chemical properties
e) a change in promoter activity
1
pf3
pf4
pf5
pf8

Partial preview of the text

Download Exam 2 with Practice Problems - Molecular Biology | MICR 302 and more Exams Molecular biology in PDF only on Docsity!

Name SS# MICR 302: Introduction to Molecular Biology Exam II Spring, 2003

Multiple Choice Questions (2 points each)

Circle the letter next to the single best answer

  1. Mutations are hereditary only if: a) they occur in germ cells b) they occur in coding sequences cells c) they occur in mitochondrial DNA d) they affect the process of transcription e) they affect the process of replication
  2. The difference between a true revertant and a second site revertant is as follows: a) A true revertant has the original DNA sequence restored b) A true revertant has an altered protein, but this works as well as the original version c) A second site revertant had two original mutations, both of which have reverted d) A second site revertant results from an insertion followed by a deletion (or vice versa) so that the overall length of the DNA is unchanged e) A second site revertant relies on having a gene duplication to replace the defective copy
  3. When DNA is repaired by the mismatch repair system: a) The parental strand is recognized because it still contains uracil from the RNA primer b) The parental strand is recognized because its GATC sequences are methylated c) The new strand is recognized because its cytosine residues are methylated d) Restriction enzymes cut out regions of the double helix that are distorted e) RNA Polymerase fills in the gaps first with temporary RNA
  4. A conservative substitution is a base substitution that results in: a) an exon being substituted with an intron during a splicing event b) a codon coding for an amino acid being substituted with a stop codon c) one amino acid being replaced with another amino acid with similar chemical properties d) one amino acid being replaced with another amino acid with very different chemical properties e) a change in promoter activity
  1. The mutagenic agent nitrous acid (or nitrites) alters DNA as follows: a) Converts one base to another by altering amino groups to hydroxy groups b) Hydrolyses pyrimidine bases off from the deoxyribose to which they were attached c) Distorts a DNA double helix by binding to base pairs d) Is mistakenly incorporated into DNA by DNA polymerase e) Inhibits DNA polymerase
  2. Sickle cell anemia and cystic fibrosis are both more common than would be expected because: a) They are both sex-linked b) They are both due to dominant mutations c) Many different mutations in different genes can cause either condition d) A single defective gene protects against certain infections e) They are due to deletions in the mitochondrial DNA
  3. Severe Combined Immunodeficiency a) Results from a recessive defect that affects the beta chain of hemoglobin b) Can be caused by a lack of adenosine deaminase c) Is caused by the clumping together of T cells d) Has been cured using genetically engineered adenovirus e) Is caused by human immunodeficiency virus
  4. Polydactyly is a condition that: a) Is due to a dominant genetic defect b) Is due to a sex-linked defect c) Causes an increase in life expectancy of roundworms d) Results from possession of extra copies of a chromosome e) Is the result of a gene duplication
  5. The normal function of the CFTR (cystic fibrosis) protein is: a) repair of DNA damage b) acting as a G-protein to transmit signals in the cell membrane c) controlling DNA replication d) a nuclease that quickly degrades abnormal mRNAs e) acting as a channel for chloride ions
  6. Human genes are usually first converted to the cDNA form for use in gene therapy. a) This is only needed for curing dominant genetic defects b) This is done by using mRNA and reverse transcriptase c) This is done by removing the introns with restriction enzymes d) cDNA is made by treating chromosomes with telomerase e) The term cDNA refers to cloned DNA
  1. During the formation of protozoan mRNA by self-splicing, the role of the internal guide sequence (IGS) is as follows: a) the IGS recognizes the 5' splice site instead of U b) the IGS recognizes the 3' splice site instead of U c) the IGS recognizes the branch site instead of U d) the IGS recognizes the small subunit ribosomal RNA e) the IGS recognizes the tail recognition site
  2. Telomeres are DNA sequences that: a) Are recognized and elongated by RNA polymerase I b) Activate the genes for ribosomal RNA c) Consist of 6 base repeats at the ends of chromosomes d) Are needed for priming DNA synthesis during chromosome replication in eukaryotic cells e) Are repeated many times and lie next to the centromeres
  3. Which of the following statements is FALSE regarding eukaryotic chromosomes: a) They are linear with a centromere and two telomeres b) They contain many repetitive sequences c) They have a single origin of replication in the centromere region d) They are larger and contain many more genes than prokaryotic chromosomes e) They have their DNA bound to histones
  4. Eukaryotic ribosomes differ from prokaryotic ribosomes in the way they translate mRNA as follows: a) In prokaryotes the start codon is always the first AUG b) In eukaryotes mRNA first binds to the large subunit of the ribosome c) In eukaryotes the mRNA binds to ribosomal RNA by its tail recognition sequence d) In prokaryotes the initiator tRNA binds to the Shine Dalgarno sequence e) In eukaryotes the mRNA is bound by Cap binding protein before it binds to the ribosome
  5. When the sequences of their ribosomal RNA are compared: a) Chloroplasts are most closely related to archaea (archaebacteria) b) Mitochondria are most closely related to the animal cell nucleus c) Chloroplasts are most closely related to the fungal cell nucleus d) Mitochondria are most closely related to the plant cell nucleus e) Chloroplasts are most closely related to bacteria
  6. When genes are regulated by steroid hormones, the steroid binds to: a) snRNP particles in the nucleus and promotes splicing of messenger RNA b) Primary transcript RNA and promotes alternative splicing c) Receptor proteins in the cytoplasm which then move into the nucleus d) Receptor proteins in the cell membrane that pass the signal on to other proteins in the nucleus e) A nuclear protein that binds to the CCAAT box that is found in the promoter region of some genes

Short answer questions

(points are indicated for each question)

  1. (4 pts) Define any two of the following terms briefly: a) snRNA; b) primary transcript; c) lariat structure; d) self splicing I. ______________ = _______________________________________
    II. ______________ = ______________________________________
  2. (4 pts) Define any two of the following types of mutations briefly : a) translocation; b) silent mutation; c) nonsense mutation; d) temperature sensitive mutation I. ______________ = ________________________________________
    II. ______________ = ________________________________________
  3. (6 pts) For each item (below) that a cloning vector carries, briefly (10 words or less each) explain the purpose of that item. a) E. coli ori b) bla gene c) MCS
  4. (2 pts) Give the full name of the protein encoded by the lacZ gene.
  5. (2 pts) How is an F' formed?
  6. (2 pts) How is an Hfr formed?

b) If the genetic transfer event is successful, will the phenotype of the recipient always change? Why or why not?

  1. (2 pts) What is the purpose of the oriT in an F plasmid? (Hint: NOT the oriV )
  2. (8 pts) Use the following items to answer the next four questions. A) Transformation B) Conjugation C) Transduction D) All of the above E) None of the above ________ The transfer event is unidirectional. ________ The donor cell must be alive. ________ The recipient cell must be alive. ________ May be achieved by transfer of RNA instead of DNA.
  1. (8 pts) You conduct a cloning experiment in which you use a cloning vector with blue/white color selection and kanamycin resistance as the selectable marker. Following insertion of your gene of interest into the cloning plasmid and transformation into an E. coli host, you plate the transformants onto an LB + kanamycin + XGal plate. For each of the following possibilities, explain how that cell (colony) would react by being plated on this type of plate. That is, would the cell survive and would it be blue or white? a) A non-transformant (a cell that was not transformed). b) A transformant containing a non-recombinant plasmid. c) A transformant containing a recombinant plasmid. For (c) above, was recombination necessary for this transformant to be formed? Why or why not?