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Transcript proteins - SharpSchool

Catalyst
SpongeBob is known for his round eyes
(R), which is dominant over an oval eye
shape (r). If he is heterozygous for his
round eye shape and marries a woman
with oval eye shape, what type of eyes
might the kids have? Use a Punnett
square to show the possibilities that
would result.
2. What are the chances of a child with a
round eye shape? ____%
3. What are the chances of a child with an
oval eye shape? ____%
1.
Genes, DNA, and Proteins
Genetics Week 4
I Can…

I CAN describe the relationship
between DNA and traits (the
genetic code).
Can you crack the code?
Use the
morse code in
the chart to
decode the
message. The
letters are
separated by
/
2. Write your
answer in
morse code.
1.
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decompressor
are needed to see this picture.
What do genes do exactly?

The main function
of GENES is to
control the
production of
PROTEINS in
cells.
What are proteins?

PROTEINS
are molecules
that help
determine
the size,
shape, color,
and other
traits of an
organism.
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decompressor
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What are proteins?

Proteins are made
up of building blocks
called AMINO
ACIDS.
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Protein Synthesis
The production of
proteins in cells is
called PROTEIN
SYNTHESIS.
 During protein
synthesis, the cell
uses information
from a GENE on a
CHROMOSOME to
produce a specific
PROTEIN.
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TIFF (Uncompressed) decompressor
are needed to see this picture.

What is a gene?

A gene is a section of a DNA molecule
that contains the information to
“code” for one specific protein.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
What is a gene?
SO… a gene is made up of a series of
DNA bases in a row.
 The bases in a gene are arranged in a
specific order--for example
ATGACTTA.

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TIFF (Uncompressed) decompressor
are needed to see this picture.
Why does the order matter?

The order of
nitrogen bases
(A, T, G, C) in a
gene forms a
GENETIC
CODE that
tells the body’s
cells what type
of protein to
produce.
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TIFF (Uncompressed) decompressor
are needed to see this picture.
What is the genetic code?
In the genetic code, every 3 DNA bases
in a row codes for one amino acid.
 For example, the base sequence CGT
always codes for the amino acid: alanine.

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TIFF (Uncompressed) decompressor
are needed to see this picture.
What is the genetic code?

The order of
the threebase code
units decides
the order of
the amino
acids in the
protein.
QuickTime™ and a
TIFF (Uncompressed) decompressor
are needed to see this picture.
Think-Pair-Share: 2 min
1.
2.
3.
What are proteins made of?
How are DNA bases and proteins
related?
Why does the order of DNA bases
matter?
Quick Quiz
1.
2.
3.
4.
5.
Amino acids
Proteins
Genes
Chromosomes
Protein synthesis
A.
B.
C.
D.
E.
Sections of DNA that
contain information to
code for one specific
protein.
Molecules that help
determine the traits
of an organism.
The production of
proteins in cells.
Very long, coiled up
DNA molecules.
The building blocks of
proteins.
What is RNA?

RNA is very
similar to DNA
except…
– It only has 1
side of the
ladder
– It has ribose
instead of
deoxyribose
– It has URACIL
instead of
THYMINE.
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decompressor
are needed to see this picture.
Quick Quiz: DNA to RNA
1.
2.
Is the sequence of
nitrogen bases to the
right part of a DNA
molecule or a RNA
molecule? Why?
Turn the following
DNA sequence into
an RNA sequence:
GATTACA
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decompressor
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mRNA
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mRNA
decompressor
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
Messenger RNA: copies coded
message from the DNA and carries
the message to the cytoplasm.
tRNA
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mRNA
decompressor
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
tRNA
Transfer RNA: carries amino acids
to the ribosome and adds them to
the growing protein.
How are proteins made?
With a table partner, write a prediction about
what is happening in each picture (1-4).
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decompressor
are needed to see this picture.
How are proteins made?
REAL LIFE
1.
2.
3.
4.
mRNA is produced
from DNA
mRNA attaches to a
ribosome
tRNA attaches to
messenger RNA
Protein production
occurs as the amino
acids on the tRNA
bond.
DEMO
1.
2.
3.
4.
Nucleus: Change DNA
code to RNA code.
Cytoplasm:Pass
mRNA to the
ribosome.
Ribosome: Attach
matching tRNA’s to
the mRNA
Chemical Reaction:
Tie the amino acids
together to make a
protein.
How are proteins made?
1. mRNA is
produced
from DNA
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decompressor
are needed to see this picture
How are proteins made?
2. mRNA
attaches to a
ribosome
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decompressor
are needed to see this picture.
How are proteins made?
3. tRNA
attaches to
messenger
RNA
QuickTime™ and a
decompressor
are needed to see this picture.
How are proteins made?
4. Protein
production
occurs as the
amino acids
on the tRNA
bond.
QuickTime™ and a
decompressor
are needed to see this picture.
Exit Slip
What are proteins?
 What are proteins made up of?
 What are genes?
 What is the main job of a gene?
 How (be specific) do genes direct the
production of proteins?

Catalyst
1.
2.
3.
4.
5.
What are chromosomes composed of?
What are genes?
What forms the “rungs” of the DNA
ladder?
Why is the sequence of bases important?
How are nitrogen base of DNA like the
letters of the alphabet?
I CAN…

I CAN describe why the order of
base pairs is important.
Mutation

A mutation is any change in a gene or
chromosome.
Mutations
Mutations can cause a cell to produce
an incorrect protein.
 As a result, the organism’s trait, or
phenotype, may be different from
what it would have normally been.

Inheriting Mutations
If a mutation occurs in a body cell,
such as a skin cell, the mutation will
not be passed on to its offspring.
 If a mutation occurs in a sex cell, the
mutation can be passed on to an
offspring and can affect the
offspring’s phenotype too!

Types of Mutations
Mutations can occur both at the DNA
base level and at the chromosome
level.
 Sometimes a cell will end up with too
many or too little chromosomes
because the chromosomes didn’t
separate properly during meiosis.

Types of Mutations

Other times, there can be a mistake
in the order or number of bases in a
gene.
– SUBSTITUTION: One base pair can be
substituted for another.
– DELETION: One base pair is removed
– ADDITION: One base pair is added.
Effects of Mutations

A mutation is harmful to an organism
if it reduces an organism’s chance for
survival.
Effects of Mutations

A mutation is helpful if it improves an
organism’s chance for survival and
reproduction in its environment.
Effects of Mutations

Whether a mutation is helpful or not
depends in part on the organism’s
environment.
Genetic Disorder
A genetic disorder is an abnormal
condition that a person inherits
through genes or chromosomes.
 Some are caused by changes in the
DNA of genes. Others are caused by
the number or structure of the
chromosomes.

Common Genetic Disorders
Cystic Fibrosis
 Sickle-Cell Disease
 Hemophilia
 Down Syndrome

Catalyst

Can mutations in DNA sequences ever
be helpful? Why or why not?
Quick Write
Look around the room at the posted
pictures. How many different skin colors
do you see?
2. What do you believe is happening at a
genetic level to produce the variety of
skin color we see in the human species?
Use your new understanding of genes and
alleles to make an educated guess.
1.
Patterns of Human
Inheritance
The inheritance of traits is rarely as
simple as in Mendel’s experiments.
 Human traits rarely come in just two
simple forms like pea plant flowers.

3 Patterns of Human
Inheritance
1.
2.
3.
Trait controlled by single gene with
2 alleles.
Trait controlled by single gene with
multiple alleles.
Trait controlled by many genes that
act together.
Single Gene with 2 Alleles
Traits that are controlled by a single
gene with just two alleles only have
two possible phenotypes or physical
appearances.
 Examples: Widow’s Peak or No
Widow’s Peak

Single Gene with Multiple
Alleles
Multiple alleles: three or more forms
of a gene that code for a single trait.
 Example: A gene that comes in three
forms: purple, white, and blue.

Single Gene with Multiple
Alleles
Even though a gene may have multiple
alleles, a person can ONLY carry 2 of those
alleles because chromosomes exist in
PAIRS (not triples, quadruples etc.)
 Each chromosome in a pair only carries one
allele for the trait.
 Example: Human Blood Type

– A, B, AB, or O.
Traits Controlled By Many
Genes
Some human traits show a large
variety of phenotypes because the
traits are controlled by many genes.
 The genes act together as a group to
produce a single trait.
 Example: Height in humans (at least
four genes), also skin, eye color, hair
color.

Traits Controlled By Many
Genes
Gummy Bear Breeding Part 2