Chp 10 Structure and function of DNA Flashcards
List the components of a nucleotide:
Nitrogenous base (Pyrimidine of purine) • Pentose sugar Phosphate group(s)
What is monomer of DNA?
nucleotides
What is the structure of DNA according to Watson and Crick?
Double helix
List three differences between DNA and RNA
instead of thymine, RNA has a similar base called uracil (U), and
• RNA contains a slightly different sugar than DNA (ribose instead of deoxyribose, accounting for the names RNA vs. DNA).
the sequence for the newly formed strand of DNA after replication.
A - T T - A C- G G - C T - A A - T C - G
What is the function of DNA polymerase?
Enzymes that make the covalent bonds between the nucleotides of a new DNA strand and can repair DNA.
Define: Transcription
Transcription is the transfer of genetic information from DNA to RNA which happens in the nucleus
• As with DNA replication, two DNA strands must first separate at the place where the process will start.
• In transcription, however, only one of the DNA strands serves as a template for the newly forming RNA molecule; the other strand is unused.
List the 3 stages of transcription.
Initiation, Elogation, Termination
A. Initiation
attachment of RNA polymerase to the promoter (beginning of the gene
B. Elongation
Synthesis of RNA, RNA strand separates from its DNA template
Termination
Polymerase reaches the terminator, signaling the end of the gene
- What is the function of a promoter and where is it present?
Beginning of the gene, starts the RNA synthesis
What is the terminator and where is it present?
A special sequence of bases in the DNA template, signals the end of the gene.
- What is the terminator and where is it present?
A special sequence of bases in the DNA template, signals the end of the gene.
What is the function of transcription factors?
Transcription is the transfer of genetic information from DNA to RNA which happens in the nucleus
• As with DNA replication, two DNA strands must first separate at the place where the process will start.
• In transcription, however, only one of the DNA strands serves as a template for the newly forming RNA molecule; the other strand is unused.
• Notice that the RNA nucleotides follow the usual base- pairing rules, except that U, rather than T, pairs with A.
What is the function of RNA polymerase?
Synthesis of mRNA
What is the function of mRNA?
Carried the genetic information copied from DNA in the form of a 3-base code, each specifies a particular amino acid.
Define Codon:
A genetic code that is a sequence of 3 bases on RNA molecule.
Define Anticodon:
Sequences of nucleotides that are complementary to codons. Found in tRNAs.
Define Mutation
any change in nucleotide sequence of a cell’s DNA . Can involve large regions of a chromosome or a single nucleotide pair. Like Sickle-cell disease
Explain why HIV virus is called a retrovirus?
because they reverse the usual DNA RNA flow of genetic information.
Which of the following correctly ranks nucleic acid structures in order of size, from largest to smallest?
chromosome, gene, codon, nucleotide
A new DNA double helix consist of
one old and one new strand
DNA replication requires…
the cooperation of over a dozen enzymes and other proteins.
How many nucleotides make up a codon?
three
The RNA that is translated into a polypeptide is ______ RNA.
messenger
During translation, what is the correct order of events that occur as an amino acid is added?
codon recognition, peptide bond formation, translocation
