DNA Flashcards
Draw a nucleotide and name the three components
Phosphate group, nitrogenous base, pentose sugar
Compare DNA and RNA
DNA has the nitrogenous base thymine whereas RNA has the nitrogenous base uracil.
DNA is double stranded whereas RNA is single stranded
DNA has the pentose sugar deoxyribose whereas RNA has the pentose sugar ribose
DNA and RNA are what type of polymer?
Nucleic acid
What is the function of helicase during DNA replication?
Helicase unwinds and unzips the DNA double helix, separating the two parent strands of the DNA molecule from one another by breaking the hydrogen bonds between complementary base pairs.
What is the function of DNA polymerase?
DNA Polymerase copies the DNA template strands, by joining up free DNA nucleotides by complementary base pairing during DNA replication.
Outline the process of DNA replication.
Helicase unwinds and unzips the DNA double helix, separating the two parent strands of the DNA molecule from one another by breaking the hydrogen bonds between complementary base pairs.
Each strand then acts as a template for synthesizing a new strand of DNA.
DNA Polymerase copies the DNA template strands, by joining up free DNA nucleotides by complementary base pairing.
Two identical copies of DNA are produced.
What is meant by the sem-conservative theory of DNA replication?
A newly formed DNA molecule consists of one original strand and one newly synthesized strand
Where does DNA replication occur in a eukaryotic cell?
Nucleus
Where does transcription occur?
Nucleus
What is the end product of transcription?
pre-mRNA
What is the definition of transcription?
DNA template strand is copied into pre-mRNA via complementary base pairing using RNA polymerase.
Pre mRNA undergoes RNA Processing. Introns are removed, a 5’ methyl cap and 3’ poly-A tail are added to form mRNA.
mRNA leaves the nucleus and goes to a ribosome.
What occurs during RNA processing?
Introns are removed. A 5’ methyl cap and 3’ poly-A-tail are added.
What enzyme is used during transcription?
RNA polymerase
What is the product formed after RNA processing?
mRNA or mature mRNA
Why are the introns spliced out?
Because they don’t code for the protein
What is the role of mRNA?
carry the code (for the protein) from the nucleus to the ribosome
A set of three nitrogenous bases in mRNA is called…
a codon
What is the monomer of a protein?
Amino acid
Draw the structure of an amino acid
Amino group, residual group, carboxyl group
What is the difference between a polypeptide and protein?
A polypeptide is a sequence of amino acids that has not been folded whereas a protein is a polypeptide that has been folded
What is meant by the genetic code being degenerate?
Multiple codons can code for the same amino acid
If a polypeptide has 90 amino acids, what is the minimum number of bases needed to code for it?
270 bases
If an mRNA molecule has 90 bases, what is the number of amino acids it could code for?
30 amino acids