2/24- Notes on DNA Ch 6
DNA stands for deoxyribonucleic
acids. It is found in the nucleus.
It is known as the “double helix”
or the “spiral staircase”
DNA is made up of bases; rungs
(steps) or nucleotides (nitrogen
bases) Complimentary bases
A- goes always with T,
C will always pair up with G.
This is called replication(unzipping stage) making and
pairing with new bases.
Adenine (A) pairs with Thymine
(T) and vice versa/ cytosine (C)
pairs always with guanine.(G)
Draw a spiral.. now make the
bases: A-T, C-G
___? -A-T- ____?
(saying… “At the guys club”)
DNA is the ”blue print” of WHO
YOU ARE! YOU ARE UNIQUE
only IDENTICAL TWINS have
the exact DNA.
Watson and Crick? What did they
do? They formed the model for
how DNA looks/ a double helix.
Who is Rosalind Franklin? She
found DNA looking at an x-ray
(diffraction)
How was DNA first discovered?
Looking at an X-ray diffraction
off the DNA molecules. Showing
spiral like shape.
Chargaff’s Rules: (%) How the
bases pair up; A-T, C-G, so the
amount of each base will equal
its’ complementary paired base:
A=50%, T= 50%
Why is DNA important? Crime
solving/ finding out about who is
the parents/offspring.
RNA- Notes: RNA stands for
ribonucleic Acids. They make
proteins. If you have NO
proteins you have no cell! There
are mRNA (messenger RNA) and
tRNA (transfer RNA) *** Look at
Mr Parr DNA on YOU TUBE
3 bases =1 codon (code for a
protein). 1 codon=1 amino acid:
Proteins are made from amino
acids (building blocks)
BASES for RNA are: A, U, C, G
Uracil is there instead of
thymine- THERE IS NO
THYMINE… So Adenine MUST
pair up with Uracil!!
So if you make a DNA sequence
of: A-T-C-C-G-G-A-A-T
What would be the RNA coding
for a protein be? (Match the
bases but remember RNA’s bases
are: A, U, C, and G (THERE IS
(NO THYMINE/ RNA has
replaced it with “U”- uracil) so
what will Adenine pair up with
now when we make an RNA/
protein strand?