Download DNA Slides - Ms. Martel

I want my class to know…
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•
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I’m learning (just like you!)
I make mistakes (just like you!)
I’m here to help you
I genuinely care about your personal growth
and academic success
Getting to know Ms.
Muirhead:
Two Truths and a Lie
a) My favourite colour is
purple
b) I own a motorcycle
c) I like to knit
a) My favourite colour is
purple
b) I own a motorcycle
c) I like to knit
a) Skiing is one of my favourite
hobbies
b) I am an only child
c) I am not from the lower
mainland
a) Skiing is one of my favourite
hobbies
b) I am an only child
c) I am not from the lower
mainland
a) Both my parents are teachers
b) I share my name with a Disney
princess
c) I am 28 years old
a) Both my parents are teachers
b) I share my name with a Disney
princess
c) I am 28 years old
What is DNA?
Where is DNA found?
DNA stands for deoxyribonucleic acid
This large molecule is present in the nucleus
of all cells in all living organisms
DNA controls:
• All the chemical changes which take
place in cells
• The kind of cell which is formed
• The kind of organisms which is produced
DNA is a very large molecule made up of a long
chain of sub-units
The sub-units are called nucleotides
Each nucleotide is made up of:
A deoxyribose sugar
A phosphate group
A nitrogenous base
There are 4 types of bases:
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Adenine (A)
Guanine (G)
Cytosine (C)
Thymine (T)
The deoxyribose, the phosphate,and one of the bases
combine to form a nucleotide
phosphate
PO4
base
deoxyribose sugar
PO4
PO4
A molecule of
DNA is formed by
millions of
nucleotides joined
together in a long
chain.
PO4
PO4
sugar-phosphate + bases
backbone
(Literally. There
are 6 billion bases
in the human
genome.)
DNA consists of a double strand of nucleotides
The sugar-phosphate backbones are on the outside
and the strands are held together by hydrogen
bonds between the bases
The two strands together twist to form a double
helix
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
PO4
The bases always pair up in the same way
Adenine forms a bond with Thymine
Adenine
Thymine
and Cytosine bonds with Guanine
Cytosine
Guanine
This is called complementary based pairing
PO4
PO4
adenine
thymine
PO4
PO4
cytosine
guanine
PO4
PO4
PO4
PO4
14
THE DOUBLE
HELIX
bases
sugar-phosphate
chain
Video: DNA Structure
• https://www.youtube.com/watch?v=qy8dk5
iS1f0
Check-In
• Which is not a component of DNA?
1.
2.
3.
4.
A nitrogenous base
An organic acid
A phosphate
A sugar molecule
What is a sub-unit of DNA
called?
1.
2.
3.
4.
Adenine
Double helix
Deoxyribose
Nucleotide
What are the correct pairings for
nucleotides?
1.
2.
3.
4.
Adenine-Guanine/Cytosine-Thymine
Thymine-Guanine/Adenine-Cytosine
Cytosine-Guanine/Adenine-Thymine
Thymine-Thymine/GuanineGuanine/Adenine-Adenine/CytosineCytosine
Which of these statements is
true?
1. Complementary base pairs are held
together with hydrogen bonds
2. The sugar phosphate backbone is in the
middle of a molecule of DNA
3. Three DNA strands make up a helix
• DNA contains thousands of genes
– Gene: a sequence of DNA that provides
instructions to make a protein
– Humans have ~23,000 genes
– These proteins contribute to our chemical and
physical traits (trait: characteristic)
DNA and Heredity
• We get half of our DNA from our mother
and half of our DNA from our father
• (How do we get this DNA?)
• This new combination of genetic material
makes us the unique individual we are!
DNA’s Role in Evolution
• DNA is the only thing that is passed from
one generation to another
• Traits that are passed from one generation
to another are called heritable traits
• The process of evolution is able to act on
these heritable traits
Video: DNA and Heredity
• https://www.youtube.com/watch?v=uXdzuz
5Q-hs
We’re all a little bit closer than
you think
• https://www.youtube.com/watch?v=OCio
HPN_QqI