Exam 4 Ch 16-21 DNA Flashcards
Erwin Chargaff Contribution
1) Base composition of DNA varies btw species 2) Number of A and T are equal to number of G and C’s
Maurice Wilkins
Studies molecular structure using X-ray Crystallography
Rosalind Franklin
Produced picture of DNA molecule using X-Rays and Chem of DNA
Watson and Crick
Built models of double helix to conform to X-Rays and Chem of DNA
Three Component parts of nucleotide
Five-carbon sugar covalently bonded to a nitrogenous base and one or more phosphate groups
Base Pairing Rules for DNA
Adenine bonds with Thymine/Cytosine bonds with Guanine
Relationship btw DNA, Chromosomes, genes, and proteins?
DNA creates chromosomes, which make genes, which are all made out of proteins.
5 and 3 as they relate to orientation of of the two strands of the double helix is called what?
Antiparallel
What type of replication process does DNA use?
Semi-conservative
Why does DNA need to be replicated?
Hereditary information is encoded and reproduced in all the cells of your body.
Identify the enzymes involved in DNA Replication-what do they do?
Helicases- untwist double helix; Topoisomerase- relieve strain by breaking, swiveling, and rejoining DNA strands
Primer
RNA Chain
Primase
synthesize RNA chain-add RNA nucleotides one at a time
Mutations
Occur when there is a change of a single nucleotide in the DNA’s template strand
Transcription
synthesis of RNA using info in the DNA-simply “rewritten” information from DNA to RNA (antiparallel)
Where does transcription take place in Eukaryotic cells?
Nucleus separate compartment
mRNA (messenger RNA)
Carries genetic message from DNA to protein (produced by transcription)
RNA Polymerase
pries two strands of DNA apart and joins together RNA nucleotides (uracil instead of thymine)
Translation
synthesis of polypeptide using mRNA info (change in language takes place and amino acids are chained together)
What is the site of translation?
Ribosomes (link amino acids into polypeptide chains)
Codons
mRNA nucleotide triplets (read in 5—>3 direction)
Anticodons
one end of tRNA which base pairs with codon on mRNA
tRNA role in translation
translates mRNA codon into a protein/amino acid
Central Dogma Chain
DNA-RNA-Protein