The Genetic Code Flashcards
Define DNA replication
DNA is copied to make more DNA
Define transcription
DNA is used as a template to make RNA
Define translation
RNA is read and proteins are made
Where does transcription occur?
In the nucleus
Where does translation occur?
In the cytoplasm
What is the basic structure of an amino acid?
NH3 (amino group) Central carbon R group Hydrogen COOH (carboxyl group)
What joins two amino acids?
A peptide bond
Where does the peptide bond form?
Between the carboxylic group of one amino acid and the amino group of the next
What kind of code is the genetic code?
Triplet code
What does triplet code mean?
Three nucleotides specify one amino acid
What is another name for a triplet?
A codon
What is the start codon in all polypeptides?
Methionine
AUG
What are the three stop codons?
UAA
UAG
UGA
What does degenerate mean?
Usually there is more than one codon for an amino acid
What is an open reading frame?
A string of sense codons that start with the codon ATG and end with a stop codon at the 3’ end
What determines which reading frame is read?
The start codon
Also the largest possible protein is always made
How many possible reading frames are there?
6
3 in each direction
How many subunits make up a ribosome?
Two
What are the two subunits of a ribosome?
The small and large subunit
What kind of ribosome is involved in protein synthesis and mRNA?
An 80s ribosome
Describe the small subunit
40s
18s rRNA
30 ribosomal proteins
Describe the large subunit
60s
28s + 5.8s + 5s rRNA
50 ribosomal proteins
2 binding sites