DNA and Proteinsynthesis Flashcards
what is a genome?
complete set of genes in a cell
what is a proteome?
full range of proteins that a cell is able to produce
what is transcription?
production of mRNA from DNA
what is the role of RNA polymerase?
joining mRNA nucleotides
what does transcription in prokaryotes result in?
results in directly the production of mRNA from DNA
what does transcription in eukaryotes result in?
results in the production of pre-mRNA and this is spliced to form mRNA
what is translation?
production of polypeptides from the sequence of codons carried by mRNA
what is mRNA?
- made during transcription
- carries genetic code from DNA to ribosomes, where it is used to make a protein during translation
what is the structure of mRNA?
- single polynucleotide strand
- groups of 3 adjacent bases = codons
what is tRNA?
- involved in translation
- carries amino acids that are used to make proteins to the ribosomes
what is the structure of tRNA?
- single polynucleotide chain
- clover shape
- hydrogen bonds between specific base pairs give clover shape
- have sequence of 3 bases at the end = anticodon
- amino acid binding site on other end
where does transcription take place?
- eukaryotic cells = nucleus
- prokaryotic cells = cytoplasm
where does translation occur?
ribosomes
what is the process of transcription in eukaryotes?
- the double helix of DNA unwinds, breaking hydrogen bonds between the DNA bases
- only one of the DNA strands acts as a template strand
- free RNA nucleotides align by complementary base pairing
- RNA uracil base pairs with adenine on DNA
- RNA polymerase joins the adjacent nucleotides
- pre-mRNA is spliced to form mRNA
what is the process of translation?
- mRNA attaches to ribosomes
- tRNA anticodons bind to the complementary mRNA codons
- tRNA brings a specific amino acid
- amino acids join by peptide bonds (condensation reaction), with the use of ATP
- tRNA is released after amino acids joins to polypeptide
- ribosome moves along mRNA to form the polypeptide
what are differences between mRNA and tRNA?
- mRNA = linear shape, tRNA = clover shape
- mRNA = has codon, tRNA = has anticodon
- mRNA has more nucleotides
- mRNA has no hydrogen bonding whereas tRNA has hydrogen bonding between complementary base pairs
