Download Deoxyribonucleic Acid (DNA)

Deoxyribonucleic Acid (DNA)
Learning Goals:
• Describe the basic structure of
deoxyribonucleic acid (DNA)
• Terms: nucleotide,
complementary base pairing
SBI3U
SBI3U ––Genetic
Genetic Processes
Processes Unit
Unit
Date:
Date: _____________________________________
_____________________________________
Deoxyribonucleic
Deoxyribonucleic Acid
Acid (DNA)
(DNA)
DNA, Chromatin & Chromosomes
Chromosomes
Chromosomes –– highly
highly coiled
coiled chromatin
chromatin // present
present during
during mitosis
mitosis (cell
(cell division)
division)
Chromatin
Chromatin –– consists
consists of
of ___________
___________ and
and __________________,
__________________, which
which provide
provide stability.
stability.
DNA
DNA is
is aa form
form of
of _____________________________
_____________________________ that
that consists
consists of
of the
the instructions
instructions for
for aa living
living cell.
cell.
DNA
1869
by
DNA was
was first
first isolated
isolated in
in–
1869
by Friedrich
Friedrich Miescher,
Miescher, but
but
• Chromosomes
highly
wasn’t
wasn’t deemed
deemed the
the hereditary
hereditary material
material of
of aa cell
cell until
until 1952
1952
(through
of
(through decades
of research
research and
and many
many scientists).
coiled
updecades
chromatin
/ scientists).
Structure
Structure of
of DNA
DNA == ____________________________
____________________________
stranded
(double
stranded and
and coiled)
coiled)
present during(double
mitosis
DNA’s
DNA’s structure
structure was
was determined
determined by
by James
James Watson
Watson and
and
Francis
Crick
in
1953,
with
the
help
of
Rosalind
Franklin.
Francis
Crick
in
1953,
with
the
help
of
Rosalind
Franklin.
(cell division)
Individual
Individual building
building blocks
blocks
(or
monomers)
of
DNA
(or monomers) of DNA are
are called
called
• Chromatin – consists
of
33
11
22
DNA and proteins,
which provide stability
chromatin
which
which consists
consists of
of 33 parts:
parts:
1.
1. ______________________________
______________________________
2.
2. ______________________________
______________________________
Sugar
Sugar and
and phosphate
phosphate groups
groups form
form the
the external
external
backbone from each strand and the nitrogenous bases
What is DNA?
• DNA is a form of nucleic acid that consists of the
instructions for a living cell.
• DNA was first isolated in 1869 by Friedrich Miescher, but
wasn’t deemed the hereditary material of a cell until 1952
(through decades of research and many scientists).
• Structure of DNA is a double helix – double stranded and
coiled (spiral)
• DNA’s structure was discovered by James Watson and
Francis Crick in 1953, with the help of Rosalind Franklin
(through decades of research and many scientists).
Structure of DNA = ____________________________
(double stranded and coiled)
Nucleotides
DNA’s structure was determined by James Watson and
Francis Crick in 1953, with the help of Rosalind Franklin.
• Individual building
blocks
monomers) of
Individual
building(or
blocks
(or monomers) of DNA are called
DNA are called
nucleotides
3
1
2
which consists2-of 3 parts:
(1)phosphate (PO4 ) group
1. ______________________________
(2)deoxyribose
sugar
2. ______________________________
(3)nitrogenous
base
Sugar and phosphate g
backbone from each st
protrude inwardly.
What is DNA?
• Sugar and phosphate groups form the external backbone
from each strand and the nitrogenous bases protrude
inwardly
• Each nucleotide consists of one of the following
nitrogenous bases:
A – adenine
T – thymine
C – cytosine
G – guanine
• Nitrogenous bases pair up in a special way called
complementary base-pairing, where:
A pairs with T
C pairs with G
The two strands of DNA attach themselves
through hydrogen bonding via their nitrogenous
bases.
Hydrogen
bonds
Homework
• Complete rest of DNA note
• Read pg. 142-149
• Pg. 151 #1-5, 9 and 10