Topic 13.1: From Code to Function Flashcards
what does from code to function mean
The DNA code needs to be read and then transformed into something functional
what is the central dogma of biology
DNA-> RNA -> Protein
how does DNA become RNA
transciption
how does RNA become proteins
translation
why is regulation of gene expression important
for bacteria = to adapt to environment
for human = genes that need to be expressed to make different cell types must be regulated, and important during development
where are genes made
nucleus
where are proteins made
cytoplasm
how does DNA in nucleus form protein in cytoplasm
mRNA out through nuclear pores into cytoplasm
when do you put a 5 prime and 3 prime end
when it is single stranded, eg: mRNA
at what direction do you make proteins
from N terminus to C terminus
what is transciptipn
simple - ‘copy the code’ from nucleotide DNA sequence to nucelotide RNA sequence
what is translation
complex - ‘changing the language’
from nucleotide to amino acid
what are the genes in front of the transcription initiation
promoter sequences - regulates where the signal for transcription initiation is along the DNA
what are the genes in front of the transcription termination
terminator sequences - regulates where the signal for transcription termination is along the DNA
what makes up a gene
coding region and the regulatory sequences around it
the promoter is always
upstream from transcription intiation
the transcription initiation is always
upstream from the coding region
termination is always
downstream from the coding region
how many genes make up haemologlobin
2 genes, one codes for alpha subunit and one codes for beta subunit
one gene codes for
one functional unit = sequence of amino acids in a polypeptide or a sequence of nucleotides in an untranslated RNA
what types of RNA are present
mRNA, rRNA, tRNA, non coding RNA, snRNA (splicing, miRNA (regulation), antisense RNA (complementary copy of mRNA)
what is the differences between RNA and DNA
RNA had C2 hydroxyl group, DNA had C2 H atom
RNA contains U instead of T
RNA is single stranded (3 and 5 prime end)
RNA can form stemloops where complementary antiparallel strands can form a mini helix
RNA can form complex 3D structures with non-standard base and other nucleotide linkage
what is ribosomal RNA
most abundant (80% of total RNA)
few kinds, many copies
small and large rRNA’s
highly conserved throughout evolution
how many rRNA do prokaryotes have
1 small
2 large
eg: 16S
how many rRNA do eukaryotes have
2 small
2 large
eg: 18S
what is tRNA
makes up 15% of total RNA
lots of kinds, many copies
small (79 nucleotides long)
each tRNA is dedicated (cognate) to one of 20 amino acids
what is mRNA
make up 2-5% of total RNA
lots and lots of kind, few copies
called ‘mRNA transcipts’
