RNA
RNA
Ribonucleic Acid
Ribonucleic Acid
Structure of RNA
Structure of RNA

Single stranded
Single stranded

Ribose Sugar
Ribose Sugar

5 carbon sugar
5 carbon sugar

Phosphate group
Phosphate group

Adenine, Uracil, Cytosine, Guanine
Adenine, Uracil, Cytosine, Guanine
Types of RNA
Types of RNA

Three main types
Three main types

Messenger RNA
Messenger RNA
(mRNA) – transfers
(mRNA) – transfers

.

During transcription, RNA polymerase binds to
During transcription, RNA polymerase binds to
DNA and separates the DNA strands. RNA
DNA and separates the DNA strands. RNA
polymerase then uses one strand of DNA as a
polymerase then uses one strand of DNA as a
template from which nucleotides are
template from which nucleotides are
assembled into a strand of mRNA.
assembled into a strand of mRNA.
mRNA
mRNA
How Does it Work?
How Does it Work?

RNA Polymerase looks for a region on
RNA Polymerase looks for a region on
the DNA known as a promoter, where it
the DNA known as a promoter, where it
binds and begins transcription.
binds and begins transcription.

RNA strands are then edited. Some
RNA strands are then edited. Some
parts are removed (
parts are removed (
introns
introns

Serine - Proline
Serine - Proline
Genetic Codes
Genetic Codes
Translation
Translation

During translation, the cell uses information
During translation, the cell uses information
from messenger RNA to produce proteins.
from messenger RNA to produce proteins.

A – Transcription occurs in nucleus.
A – Transcription occurs in nucleus.

B – mRNA moves to the cytoplasm then to the
B – mRNA moves to the cytoplasm then to the
ribosomes. tRNA “read” the mRNA and obtain
ribosomes. tRNA “read” the mRNA and obtain
the amino acid coded for.
the amino acid coded for.

C – Ribosomes attach amino acids together
C – Ribosomes attach amino acids together
forming a polypeptide chain.
forming a polypeptide chain.

D – Polypeptide chain keeps growing until a
D – Polypeptide chain keeps growing until a
stop codon is reached.

Frameshift Mutation
Frameshift Mutation
–
–
Inserting
Inserting
an extra
an extra
nucleotide or
nucleotide or
deleting
deleting
a nucleotide
a nucleotide
causes the entire code to “shift”.
causes the entire code to “shift”.
Gene Mutation
Gene Mutation
Chromosomal
Chromosomal
Mutations
Mutations

Deletion
Deletion
– Part of a chromosome is deleted
– Part of a chromosome is deleted

Duplication
Duplication

In simple cells (prokaryotic) lac genes
which are controlled by stimuli, turn
which are controlled by stimuli, turn
genes on and off.
genes on and off.

In complex cells (eukaryotic) this process
In complex cells (eukaryotic) this process
is not as simple. Promoter sequences
is not as simple. Promoter sequences
regulate gene operation.
regulate gene operation.
Review
Review