Download Sc9 - a 3.1(teacher notes)

Learning outcomes:
1 I can describe the relationship among chromosomes, genes and DNA, and their role
in storing genetic information.
3.1 DNA – Transmitter of Genetic Code
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DNA video - http://www.youtube.com/watch?v=8kK2zwjRV0M
Characteristics are passed on from one generation to
another within a species through the genetic code of
the parents.
This genetic code is called DNA
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This molecule is called: desoxyribonucleic acid
(DNA)
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It is a blueprint passed on from parents to offspring.
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It is found in the cell nuclei.
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It is responsible for variation among living things that
reproduce sexually.
Discovered in 1944 by James Watson and Francis Crick and
Rosalind Franklin( X ray expert)
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DNA has a specific shape and is
made by specific proteins.
o SHAPE: like a ladder
twisted into a spiral.
o The hand rails are
composed of phosphates
and sugars.
o The steps of the ladder are
proteins: guanine (G),
cystosine (C), adenine (A)
and thiamine (T).
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The sequence of the proteins creates a code that the cell is
able to interpret.
o This is called the genetic code.
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Quick video: http://www.youtube.com/watch?v=qy8dk5iS1f0
Quick video #2:
http://www.youtube.com/watch?v=cwfO6SzGaEg&feature=related
***Use Kagan strategies:
Formations – in groups, students must create a formation that represents what DNA looks
like at microscopic level.
 Each cell contains a lot of DNA.
To be able to fit it all in cells, they
are rolled up together in what we
call :
o Chromosomes.
 Every human
contains 46
chromosomes:
 Different living organisms have different quantities of
chromosomes.
 These chromosomes are in pairs.
Video: where do genes come from?
 A single gene is an uninterrupted segment of DNA, which
contains the coded instructions for the organism
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Genes are located in the chromosomes
Each chromosome has numerous gene locations
Genes come in pairs
Both genes in a pair
carry DNA
instructions for the
same thing
Specific characteristic
genes occupy
matching locations on
the two chromosomes
DNA code may not
be exactly the same
in both locations
Offspring inherit genes from both parents. The genes exist in an array
of possible forms that differ as to their exact DNA sequence.
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These variations in forms are called alleles.
The ultimate combination of the chromosome pair is what makes
the variation possible - combining the different variations of
different characteristics to create a unique variation.
Graph analysis
1. What is the subject?
2. What conclusion can be made with this diagram?
3. What is the manipulated variable? Controlled variables? Responding
variable?
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Activity: How DNA is organized! Create a project that explains to the
class how DNA is organized. Ex: Kids book, A comparison, a 3-D diorama
An analogy, etc…
Optional: Answer questions from page 45.
Optional: Do vocabulary of words in Bold.