BIOL 2303 Lecture Notes - Lecture 26: Deoxyribose, Ribosomal Rna, Chromosome

12 views2 pages

pearferret848

8 Jul 2020

School

Department

Course

Professor

For unlimited access to Class Notes, a Class+ subscription is required.

Document Summary

Lecture 26: dna is synthesized in one chemical direction called 5" to 3 " (5" is phosphate end" 3" is hydroxyl end of deoxyribose). At the replication fork, the leading strand is synthesized continuously and the lagging strand, discontinuously . mismatched bases before continuing dna synthesis. Errors only occur approximately 1 time for every 10^10 bases added: dna polymerase proofreads new molecules of dna and removes, each daughter bacterium receives a chromosome identical to the parent"s (approximately 18 mins for replicating e. coli genome). Rna and protein synthesis: during transcription , the enzyme rna polymerase synthesizes a strand of rna from one strand of double-stranded dna, which serves as a template , rna is synthesized from nucleotides containing the bases a,c,g,and. U , which pair with the bases of the dna antisense strand: the starting point for transcription, where rna polymerase binds to.

Related Questions

1. The DNA strand that is synthesized continuously is called thelagging strand.

2. The DNA strand that is synthesized discontinuously is called theleading strand.

3. DNA ligase joins adjacent Okazaki fragments together into acomplete strand.

4. DNA polymerases cannot initiate synthesis of a new DNA strand;they can only add bases to an existingstrand.

5. DNA polymerase I removes the RNA primer and synthesizes ashort sequence of DNA that will base pair with the parent strand ofDNA.

magentaantelope571

1. During DNA replication, proteins unwind the DNA duplex, and separate the DNA strands. Those proteins include:

a.) DNA polymerase and ligase

b.) Single-stranded DNA binding and protein primase

c.) Helicase and DNA polymerase

d.) Helicase and single-stranded DNA binding protein

2. What determines the nucleotide sequence of the newly synthesized strand during DNA replication?

a.) The particular DNA polymerase catalyzing the reaction

b.) The relative amounts of the four nucleotide triphosphates (ATP, GTP, CTP, and TTP) in the cell

c.) The nucleotide sequence of the template strand

d.) The primase used in the reaction

e.) Both A and D

3. The leading and the lagging strands differ in that

a.) The leading strand is synthesized in the same direction as the movement of the replication fork, and the lagging strand is synthesized in the opposite direction.

b.) The leading strand is synthesized by adding nucleotides to the 3â hydroxyl (OH) end of the growing strand, and the lagging strand is synthesized by adding nucleotides to the 5â phosphate (PO4) end.

c.) The leading strand is synthesized continuously, whereas the lagging strand is synthesized in short fragments that are ultimately stitched together.

d.) Both A and B

e.) Both A and C

1.When a protein binds to DNA at a site defined by a particular nucleotide sequence, with which parts of the DNA does the protein primarily interact?

A. the phosphate and deoxyribose groups in the DNA backbone

B. the phosphate and deoxyribose groups in the DNA backbone, and hydrophobic interactions with the nucleotide bases

C. nucleotide bases within the major grooves of the DNA

D. nucleotide bases within the major and minor grooves of the DNA

E. none of the above

2. Which of the following proteins binds to DNA with sequence specificity?

A. POI Ill holoenzyme

B. DnaA

C. DnaB

D. Dam methylase

E. Both B and D

3. Which of the following is NOT a functional parallel among all known cellular systems of DNA replication?

A. Replication is initiated at specific sites

B. Replication is continuous on the leading strand and discontinuous on the lagging strand

C. DNA replication is semiconservative

D. Replication forks move away from the origin in one direction

E. Nucleases, polymerases and ligases replace RNA primers with DNA and seal the remaining nick

4. A DNA polymerase cannot synthesize a DNA strand de novo (from the beginning) from a mixture of dNTPs. Which of the following explains the role of the primer in the reaction promoted by this enzyme?

A. The primer is an initiation protein with attached nucleotides that binds to the template and to which new nucleotides are added to the 3 ' end.

B. The primer is an initiation protein with attached nucleotides that binds to the template and to which new nucleotides are added to the 5' end.

C. The primer is a preexisting strand of RNA or DNA to which new nucleotides are added to the 3' end.

D. The primer is a preexisting strand of RNA or DNA to which new nucleotides are added to the 5' end.

E. The primer is a preexisting strand of DNA synthesized by DNA pol I, prior to replicative DNA synthesis by DNA pol Ill.

5. Universal features of DNA polymerases include:

A. 5'-3' exonuclease function.

B. Formation of an 'closed' conformation of the polymerase when the template-nucleotide base pair is correct.

C. Use of a single magnesium ion to orient reacting molecules and assist in dissipation of the negative charge that develops during nucleotidyl transfer.

D. Alignment of conserved residues in the active site for attack of the DNA primer by the 3 'OH on the incoming nucleotide.

E. Continuous unbinding and rebinding of the polymerase to the DNA template as each nucleotide is added.

byzantiumscorpion425

BIOL 2303 Lecture Notes - Lecture 26: Deoxyribose, Ribosomal Rna, Chromosome

Document Summary

Get access

Related Documents

BIOL 2303 Lecture Notes - Lecture 13: Prokaryotic Large Ribosomal Subunit, Prokaryotic Small Ribosomal Subunit, 23S Ribosomal Rna

BIOL 2303 Lecture Notes - Lecture 7: Hfq Protein, Signal Transduction, Virulence Factor

BIOL 2303 Lecture Notes - Lecture 4: Semiconservative Replication, Okazaki Fragments, Operon

Related Questions