Sections within a gene
CODONS
TAC
Codes for protein
Codon base triplets
Examples ATC CCG
Stop CodonStart Codon
ATT, ATC, or ACT
Codons, Amino Acid & Protein
One codon codes for one amino acid
EX: ACG = amino acid (threonine)
CGC = amino acid (arginine)
GGA = aminio acid (glycine)
A sequence of amino acids is a protein
ACG
GGA
GGC
CCA
AAC
CCG
GCCCGC
Threonine
Arginine
Glycine
Glycine
Proline
Asparagine
Proline
Alanine
Amino Acid
Protein
RNA
– Ribonucleic acid
– Single stranded
– Sugar is ribose
– Uracil replaces thymine
– Types of RNA
– mRNA – messenger – transcription
– tRNA – transfer – translation
– rRNA – ribosomal – makes up part of ribosome
DNA vs RNA
Contains deoxyribose
sugar
Is double stranded
Bonds A-T and C-G
Never leaves the nucleus
Contains ribose sugar
Is single stranded
Bonds A-U and C-G
Can leave the nucleus
How Does RNA Help?
DNA – contains the master code
tRNA
towing
Amino acid
mRNA
Protein
factory
tRNA, transfer RNA
carries amino acids
rRNA, ribosomal RNA
guides the process in the
ribosome
mRNA, messenger RNA
copies/carries the DNA code
Chromosome DNA
gene expression
mRNA copies DNA in nucleus –
transcription
Takes copy to ribosome
tRNA brings amino acids to
ribosome – translation
Transcription Translation
What does the chain of amino acids represent?
Threonine
Arginine
Glycine
Glycine
Proline
Asparagine
Proline
Alanine
Polypeptide Chain – A Protein
What is the monomer (subunit) for protein?
What are the functions of protein?
Name examples of proteins.
amino acids
structure or support; enzymes speed up
chemical reactions
muscles, hair, cartilage, nails
SUMMARY Transcription Translation
G
A
C
G
A
U
A
A
T
T
T
C
C
A
G
G
C
G
DNA mRNA
A U U
Amino Acid
tRNA Protein
Occurs in the Occurs in the
DNA
DNA has the
master code
mRNA is made,
copying DNA’s code
A protein is made
PROTEIN REVIEW
What is the monomer (subunit) for protein?
amino acids
What are the functions of protein?
structure or support; enzymes speed up chemical reactions
Name examples of proteins.
muscles, hair, cartilage, nails
