Download Putting it Together: DNA Functions

Connect!
• Why does DNA remain in the nucleus?
• What are the two jobs of DNA?
Putting it Together: DNA Functions
•Genes are Chemical Instructions
A gene is a length of DNA. DNA is a long list of
instructions on how to put the organism together and
make it work.
Each separate gene is a specific chemical instruction to a
particular type of cell.
Cells make proteins by stringing amino
acids together in a particular order.
There are only about 20 different amino acids but they
make up millions of different proteins.
Genes simply tell cells
what order to put the
amino acids together.
The sequence of bases
or order determines
what proteins the cell
produces, which in turn
determines what type of
cell it is, for example
skin cell or nerve cell.
How Does DNA Control A Cell?
Sequence of bases in a gene
Sequence of amino acids
Shape of protein
Type of cell and activities it carries out
Collagen is a protein found in
bones, tendons and cartilage, so it
needs to be strong.
The chains are tightly coiled to form
a strong, fibrous structure.
It is formed by bone and cartilage
cells using a specific collagen gene,
which is a specific sequence of
bases, which produce a specific
sequence of amino acids, which
fold into a specific shape…the
twisted, chain of collagen. The
shape gives the protein its function.
Insulin is a hormone that reduces
blood glucose levels.
It’s a small, globular protein, so it is
easily transported in the blood.
It is formed by pancreas cells using a
specific insulin gene, which is a
specific sequence of bases, which
produce a specific sequence of amino
acids, which fold into a specific
shape…the small, glob of insulin. The
shape gives the protein its function.
Chunk!
•What are the 2 functions of DNA?
•What is a gene?
•What kind of instructions are encoded in the DNA?
•How do cells make proteins?
•What do genes “tell” the cell?
•What does the sequence of bases determine?
•What does the sequence of amino acids determine?
•What does the shape of the protein determine?
•How does DNA control
a cell?
•Explain, using either
collagen or insulin as
an example.
•How do organisms
end up with different
types of cells?
Get it?
Dog genes!