Transcript DNA
Decode
26-A
17-J
8-S
25-B
16-K
7-T
24-C
15-L
6-U
23-D
14-M
5-V
22-E
13-N
4-W
21-F
12-O
3-X
20-G
11-P
2-Y
19-H
10-Q
1-Z
18-I
9-R
Yes, It’s a Lobster
• What makes lobsters red?
• What causes the color change?
Nitrogenous Bases(A) Adenine - blue
3
(G) Guanine – brown
3
3
(T) Thymine – gray
3
(C) Cytosine – white
Sugar – orange
12
Hydrogen bond – red
6
12
Phosphate – yellow or
orange
DNA Models
What Does DNA Look Like?
With the person sitting next to you:
Make 6 nucleotides using any combination of the 6 nitrogen bases.
(Show me - 1 point)
Link them together at the deoxyribose and phosphate connections. (Show
me - 1 point)
Make 6 complimentary nucleotides to the ones you just made. Link
these nucleotides together at the deoxyribose and phosphate connections.
(Show me - 1 point)
Now add a hydrogen bond to each of your original nucleotides and
connect them with the complimentary strand. (Show me - 1 point)
Draw the DNA model you just made.
How Does DNA Replicate?
With another table:
1. Keep one of the DNA molecules that was made intact. Disassemble
the other DNA molecule into separate nucleotides.
2. “Unzip” the DNA by separating the two strands at the hydrogen
bonds. Keep the top hydrogen bond attached. Open the sides of the
DNA and make a diagram.
3. Starting at the bottom, add the correct nucleotides to each side by
following the rules for base-pairing. Add three nucleotides to each
side.
4. Make a drawing of your DNA molecules. If you were to complete all
the nucleotide pairings, would the two new strands of DNA be exact
copies of the one original strand?
Types of Mutations
1. Substitution
A substitution is a mutation that
exchanges one base for another (i.e., a
change in a single “chemical letter”
such as switching an A to a G). Such a
substitution could:
A.
change a codon to one that encodes a
different amino acid and cause a small
change in the protein produced. For
example, sickle cell anemia is caused by
a substitution which alters one amino
acid in the protein responsible for
making hemoglobin.
B.
change a codon to one that encodes the
same amino acid and causes no change
in the protein produced.
C.
change an amino-acid-coding codon to a
single “stop” codon and cause an
incomplete protein.
Types of Mutations
2. Insertion
Insertions are mutations in
which extra base pairs are
inserted into a new place in the
DNA.
Types of Mutations
3. Deletion
Deletions are mutations
in which a section of DNA
is lost, or deleted.
Using Genetic Knowledge
Genetic Engineering: manipulating individual
genes within organisms
Genetic Identification: using the unique
patterns found in an individual’s DNA to
identify how closely related two organisms are
to each other