Ch8 DNA Flashcards
1
Q
Gene
A
- base sequence of DNA
- codes for a polypeptide
- codes for functional RNA
- found at specific locus
1
Q
Degenerate code
A
amino acids are coded for by more than one triplet
2
Q
Non-overlapping code
A
each base in the sequence is only read once
3
Q
Universal code
A
each triplet codes for the same amino acid in all organisms
4
Q
Triplet code
A
- 20 different amino acids
- 4 bases in DNA
- 4^2= 16 is inadequate
- 4^3 = 64 codes
- amino acids coded for by 3 bases
5
Q
Allele
A
alternative forms of a gene
6
Q
Genome
A
complete set of genes in a cell
7
Q
Proteome
A
complete set of proteins produced by the genome
8
Q
Structure mRNA
A
- long strand
- single helix
- contains exons
- has codons
9
Q
Structure tRNA
A
- small molecule
- single-stranded
- has anticodon specific to amino acid
- clover leaf shaped
- has paired bases
10
Q
Codon
A
sequence of 3 bases that codes for amino acid
11
Q
Transcription
A
- DNA helicase at specific DNA region causes strands to separate
- free RNA nucleotides pair with complementary nucleotides on template strand
- RNA polymerase moves along strand and joins sugar-phosphate backbone
- detaches at stop codon
- produces pre-mRNA
- DNA reforms
12
Q
Splicing
A
- remove introns(non-coding genes)
- if not, would produce non-functional polypeptides
- produces mRNA
- leave by nuclear pore
13
Q
Translation
A
- ribosome attaches to codon on mRNA
- tRNA with complementary anticodon binds to codons
- each have specific amino acid attached
- ribosome moves along mRNA, brining together tRNA
- enzyme and ATP create peptide bond between amino acids
- ends at stop codon
14
Q
Prokaryotic DNA
A
- no introns
- circular
