Transcript DANDY Deoxyribonucleic Acid

DANDY
Deoxyribonucleic Acid
ALL CELLS HAVE DNA…
• Cells are the basic unit of structure
and function of all living things.
– Prokaryotes (bacteria)
– Eukaryotes (animals, plants, etc.)
Deoxyribonucleic Acid
• DNA is found in
the nucleus (of
eukarytotes).
• Remember…the
nucleus is the
“control center”
of the cell.
DNA is found in three forms…
• Chromatin - Single strands of DNA found in
the nucleus when the cell is NOT dividing.
• Chromatid - Single copy of condensed DNA
that is coiled and wound up prior to division.
• Chromosome - Two copies of DNA (two
chromatids) connected prior to cell division.
DNA is the code of life…
• Genes - segments of
DNA that code for
specific proteins and
therefore specific traits.
D.N.A.
• Deoxyribonucleic Acid
- Hereditary material
- Double helix - a “twisted ladder” of
nucleotides.
Nucleotides:
• Sides of the ladder
A. Sugar
B. Phosphate
• Steps of the ladder
C. Nitrogen Base
* Cytosine
* Guanine
* Adenine
* Thymine
T
A
C
G
G
C
The Bases Pair…
• C always goes with G.
– they both have curves.
• A always goes with T .
– they both are made of sticks.
HOW DOES THE DNA
“MAGIC” WORK?
• DNA makes RNA
• RNA makes protein
• Which of our friendly organelles makes
protein?
• Where in the cell are they?
• Where are the chromosomes?
So what is RNA?
G
• R.N.A - Ribonucleic Acid
C
• Just like DNA except:
** Ribose (sugar)
** Single Stranded
** Uracil instead of Thymine
A
U
How does DNA work?
•
The DNA is Read.
1. The nucleus gets a chemical
signal to make a protein.
2. The DNA is opened (unzipped)
where the gene starts.
How does DNA work?
3. mRNA pairs up with
the DNA template.
4. The DNA closes and
the mRNA strand
leaves the nucleus.
Let’s Try A DNA Example:
1. Fill in the matching bases for the DNA
strand
TTCGAG-
Let’s Try A DNA Example:
1. Fill in the matching bases for the DNA
strand
T-A
T-A
C-G
G-C
A-T
G-C
RNA Example
TTCGAG-
-A
-A
-G
-C
-T
-C
2. Fill in the new
mRNA strand along
the left side of the
DNA
RNA Example
T-A
T-A
C-G
G-C
A-U
G-C
-A
-A
-G
-C
-T
-C
2. Fill in the new
mRNA strand along
the left side of the
DNA
Completed RNA
3. Write the new mRNA strand that
moves into the cytoplasm
Completed RNA
3. Write the new mRNA strand that
moves into the cytoplasm
A
A
G
C
U
C
How Powerful Proteins Are Made…
1. The mRNA
leaves the
nucleus and
attaches itself
to a ribosome.
2. The ribosome
reads the RNA
3 bases at a
time (codon).
Ribosome
mRNA
A
A
G
C
U
C
codon
How Powerful Proteins Are Made…
3. For each
codon, an
amino acid is
attached to the
ribosome to
form a chain of
protein.
CCG
mRNA CODES FOR AMINO ACIDS
Third Base
U
C
A
G
First
Base
Second
Base
U
U
C
A
G
Phenylalanine
Serine
Tyrosine
Cysteine
Phenylalanine
Serine
Tyrosine
Cysteine
Leucine
Serine
Stop Codon
Stop Codon
Leucine
Serine
Stop Codon
Tryptophan
C
U
C
A
G
Leucine
Proline
Histidine
Arginine
Leucine
Proline
Histidine
Arginine
Leucine
Proline
Glutamine
Arginine
Leucine
Proline
Glutamine
Arginine
A
U
C
A
G
Isoleucine
Threonine
Asparagine
Serine
Isoleucine
Threonine
Asparagine
Serine
Isoleucine
Threonine
Lysine
Arginine
Methionine
Threonine
Lysine
Arginine
G
U
C
A
G
Valine
Alanine
Aspartic Acid
Glycine
Valine
Alanine
Aspartic Acid
Glycine
Valine
Alanine
Glutamic Acid
Glycine
Valine
Alanine
Glutamic Acid
Glycine
How Powerful Proteins Are Made…
4. After reading the
RNA the ribosome
sends the protein
chain to the golgi
complex to be
packed and
shipped.
Shipped
to Golgi
Let’s continue our
example…
AARockin’
GRibosome
CUCmRNA -
Amino Acids
Let’s continue our
example…
AARockin’
GRibosome
CUCmRNA -
Lysine
Leucine
Amino Acids
Let’s try the whole thing!!!
TACGGACCTD.N.A
Rockin’
Ribosome
R.N.A
Amino Acids
Let’s try the whole thing!!!
T-A
A-T
C-G
G-C
G-C
A-T
C-G
C-G
T-A
D.N.A
Rockin’
Ribosome
R.N.A
Amino Acids
Let’s try the whole thing!!!
T-A
A-T
C-G
G-C
G-C
A-T
C-G
C-G
T-A
D.N.A
Rockin’
Ribosome
A
U
G
C
C
U
G
G
A
R.N.A
Methionine
(start codon)
Proline
Glycine
Amino Acids