Transcript Document

Genes are read and copied before use!
The instructions that are needed by
the cell are copied from the DNA
into a similar molecule called RNA
DNA: DeoxyriboNucleic Acid
RNA:
RiboNucleic Acid
The nucleus READS the genes and
sends INSTRUCTIONS in the form of
RNA “messages”
Nucleus
Each gene is copied into RNA
when it is needed by the cell
What Kind of Stuff Are You Made Of?
Nerve cells
Muscle cells
Cells: The fundamental unit of life
The building blocks of bodies
We are each made of 100 trillion cells!
Red blood cells
Cells lining the
small intestine
Fat cells
Cells lining a tubule
http://gened.emc.maricopa.edu/bio/bio181/BIOBK/BioBookAnimalTS.html
Cell types in the stomach
Different Cell Types Make Different Organs
Nerve cells
Muscle cells
Each cell type does a different job
What makes cells different
They must not get “mixed up”!
from each other?
What makes these cells differentiate?
Red blood cells
Gene Expression
Cells lining the
small intestine
Cells lining a tubule
Fat cells
http://gened.emc.maricopa.edu/bio/bio181/BIOBK/BioBookAnimalTS.html
Cell types in the stomach
Flow of Genetic Information: DNA to RNA to Protein
DNA
(GENE)
mRNA
mRNA
DNA is copied into RNA:
DNA letters copied into RNA code.
AAAAAAAAAA
Messenger RNA
The RNA code specifies the order of amino
acid building blocks in the protein.
PROTEINS
The amino acid chain folds to make a
functional 3D protein.
A DNA Spelling Mistake Can Alter the Protein Chain
START ADD
ADD
ADD
ADD
ADD
ADD
ADD
STOP
ATG TTC AGG CCA AAT TTT GTC GCG UAA GGA ATT
Spelling Mistake
The DNA “word” TTC is changed to TTT
ATG TTT AGG CCA AAT TTT GTC GCG
TTC to TTT spelling change causes a different protein building
block to be inserted in the second position. That is all it takes.