chapter 2 Flashcards
what are the differences between DNA and RNA?
- RNA has ribose not deoxyribose sugar, meaning 1 extra oxygen atom
- RNA is single stranded, DNA double stranded
- RNA has uracil, while DNA has thymine
ends of a double helix
one 5’ (phosphate) one 3’ (sugar)
mRNA vs rRNA vs tRNA
mRNA is the result of transcription, goes to places to synthesise proteins
rRNA lives in ribosomes, tRNA translates mRNA into amino acids forming polypeptide chains
how does transcription occur, including processing
- RNA polymerase enzyme breaks apart DNA from the promoter to the terminator and attatches free complementary pairs to the template strand to form a pre-mRNA strand.
- a 5’ methyl-G cap is added, and poly-A tail to the 3’ end
- introns are spliced
the steps of translation
- mRNA binds to a ribosome, and a tRNA’s anticodon binds to its codon.
- the attatched amino acids of many tRNAs form a polypeptide chain.
exon vs intron
exon is a coding region, intron is not
promotor in eukaryotes is often:
TATAAA
what protein splices introns?
spliceosome
anticodon vs codon
the opposite of a codon, codon codes for 1 amino acid
polypeptide chain
a string of amino acids bonded togetehr
silent mutation
doesn’t affect amino acid sequence
coding strand
same as RNA but with T not U
template strand
what RNA binds to and is the opposite of
direction of movement in transcription
5’end to 3’end (nucleotides added to 3’end)
alternative splicing
exons being excluded or included to make different mature mRNA ! (NO ORDER SWITCHIGN THOUGH JUST THINGS LEFT OUT)