Nucleic acids 2.3 Flashcards
What does DNA stand for?
Deoxyribonucleic acid
What does RNA stand for?
Ribonucleic acid
What does DNA consist of?
- deoxyribose sugar
- phosphate
- bases
How many rings does a purine have?
2
How many rings does a pyrimidine have?
1
Which bases are purines?
Adenine and guamine
Which bases are pyrimidines?
Cytosine, thymine and uracil
What elements does nucleic acid contain?
P, C, H, O, N
How many hydrogen bonds form between A and T?
2
How many hydrogen bonds form between C and G?
3
In what directions do the 2 strands of DNA run in comparison with eachother?
Antiparallel
What shape does DNA form?
Double helix
What is all the DNA within a cell called?
Genome
What is a nucleotide?
- molecule consisting of a 5 carbon sugar, a phosphate group and a nitrogenous base
- the monomer from which nucleic acids are made
What does ATP consist of?
Adenine, ribose and 3 phosphate groups
What does ADP consist of?
Adenine, ribose, 2 phosphate groups
What does the enzyme gyrase do?
Unwinds the DNAs double helix
What does the enzyme helicase do?
Unzips the DNA by breaking the hydrogen bonds between bases
What does the enzyme DNA polymerase do?
catalyses the reaction between the phosphate and the sugar to join them together and form phosphodiester bonds
What does the enzyme ligase do?
Joins together the strands of the lagging strand
In what direction does DNA polymerase add the complimentary bases?
In a 5’ to 3’ direction
What does semi conservative mean?
1 old copy and 1 new copy
What does conservative mean?
2 new copies and 2 old copies
What does dispersive mean?
Mixture of both copies
What is mRNA?
Messanger RNA
What is tRNA?
Transfer RNA
What is rRNA?
Ribosomal RNA
What is RNA?
Single strand of DNA containing uracil
What does mRNA do?
Transcribes DNA code
What does rRNA do?
Primary component of the ribosome
What does tRNA do?
Caries amino acids to a proper position during translation
What is a codon?
A triplet of bases
What binds to the codons?
The anticodon loop
What does universal mean?
The same codons code for the same amino acids in all organelles
What does degenerate mean?
Some amino acids can be coded for by multiple different codons
What does non overlapping mean?
Each base is only part of one codon and that each codon is read one at a time in order
What happens during transcription?
- gyrase unwinds DNA
- helicase unzips DNA
- RNA polymerase adds complimentary base pairings creating a copy strand from the template strand in a 5’ to 3’ direction
- mRNA passes out the nucleus and attaches to a ribosome
What happens during translation?
- tRNA molecule finds the place where the anti codon loop forms temporary H bonds with the complimentary RNA codon
- tRNA the leaves, leaving behind an amino acid
- ribosome moves along the RNA allowing adjacent amino acids to for peptide bonds
- ATP is needed for protein synthesis
What is a gene?
A section of DNA that codes for a protein
