MUTATIONS!
What might be reasons for the
unusual characteristics in the next
photos?
http://news.sky.com/skynews/Home/Sky-NewsArchive/Article/200806412815981
http://www.tropicaldesigns.com/images/watson2.jpg
http://www.msnbc.msn.com/id/10792937/
What are Mutations?
Brain Storm any words,
definitions, or examples for
In the living cell, DNA undergoes frequent chemical change,
especially when it is being replicated. Most of these changes are
repaired
quickly ____________.
Those that are not result in a mutation
___________.
DNA
Thus, mutation is a failure of _______
repair.
A ______________
mutation
is permanent change in the DNA ___________
sequence
gene
of a _______.
Mutations in a gene’s DNA sequence can alter the
amino acid
protein
____________
____________sequence of the ________________
encoded by the gene. Like words in a sentence, the DNA sequence
determines
of each gene _______________
the amino acid sequence for the
____________
protein
it encodes. The DNA sequence is interpreted in
nucleotide
codons
groups of three ______________
bases, called __________.
How do genetic traits effect an organism’s
survival?
harmful
1. A mutation is ___________
to an organism’s survival if it reduces
survival
the organisms chance for _______________
and
reproduction
________________.
2. Whether a mutation is harmful to an organism depends partly on
reproduction
the organism’s________________.
http://cellar.org/iotd.php?threadid=7787
(SE)Would the color of this cub be
considered harmful in the wild? How
about in a zoo or wildlife sanctuary? Why ?
(M) What is a synonym for “Mutation”?
(U) What are similarities between harmful
mutations and parasitism, a symbiotic
relationship which you learned about
earlier this year ?
(I) How would you parent this cub to
ensure its safety if you were this Mama
bear ?
http://cellar.org/iotd.php?threadid=7787
Types of Mutations:
1. Harmful- reduces the organism’s chances for survival and reproduction
2. Helpful- increases the organism’s chance for survival and reproduction
3. Neither- (neutral) no effect either way
http://www.virginmedia.com/digital/features/hybrid-animals.php
Mutations can occur in two different types of cells:
1. Somatic (body) cells
2. Gamete (sex) cells
Somatic Cells
Mutations that occur in somatic (body) cells usually result in killing that body cell only. These
usually do not affect the individual and can NOT be passed on to offspring. An exception is if
the mutation occurs to the DNA that controls regulations of the cell cycle. This can result in
cancer.
Gamete Cells
Mutations that occur in gamete (sex) cells means that every cell of the fetus will have that
mutation.
Gamete mutations usually affect the individual with some genetic disorder.
They can be passed on to offspring
There are 2 types of Mutations that occur in gamete cells.
1. 2 types of Gene Mutations
A. Point Mutations:
a single point in the DNA sequence is affected.
Substitution: one base is changed into another base
Point Mutations usually affect no more than a single amino acid.
The protein may be slightly affected or not at all.
THE FAT CAT ATE THE RAT
THE FAT CAT ATE THE HAT
2.
Frameshift Mutation: a single gene or nitrogen base is
deleted or added from the mRNA sequence causing a shift in
the “reading frame” of the genetic message.
•
It can be an insertion in which one base is inserted in the DNA
sequence.
•
It can be a deletion in which one base is deleted in the DNA
sequence.
•
These are usually more dramatic than Point Mutations.
Frameshift Mutations may alter protein so much that it is
unable to perform its normal functions.
THE FAT CAT ATE THE RAT
TEF ATC ATA TET HER AT
1. Pretend you are a DNA mechanic. How might you “fix” this kitten?
(SE)
2. How do you think that this type of mutation occurs? (M)
http://www.brisbanetimes.com.au/photogallery/2008/11/21/1226770686660.html
5 types of Chromosomal Mutations:
1. Deletion: involves the loss of all or part of a chromosome
2. Duplication:involves the production of extra copies of parts of the
chromosome.
3. Inversion: reverses the direction of parts of a chromosome
4. Translocation: : when one part of a chromosome breaks off and
attaches to another chromosome
5. Non-disjunction: means “not coming apart” when homologous
chromosomes fail to separate properly during meiosis. (results in
abnormal numbers of chromosomes)
Monosomy- a person is
missing a copy of a chromosome
Trisomy- a person has an extra copy of a chromosome
Neutral? Helpful?
Harmful?
http://erikpemberton.org/page/2/
This calf is from Chernobyl.
How might you respond to a neighbor’s
suggestion to put your “mutated” puppy
to sleep (euthanize) or at the very least
have surgery to remove its extra limb?
What positives could you give to counter
their negative statements? (I)
What are some issues that this
calf might encounter
considering its mutations? (U)
http://www.mahalo.com/5-legged-puppy
(M) Describe the phenotypes of the mutated vegetables. (I) Imagine you
are a farmer. How do you feel about your crop of mutated vegetables?
(SE) If you were selecting vegetables from the grocery store, would you
buy these? (U) What happened to these vegetables & fruit?
http://onemansblog.com/category/food/page/2/
Ticket out the door
3-What were the 3 types of
mutations? (M)
2- What are 2 ways that organisms
can mutate? (M)
1- Name 1 positive effect of
mutations. (I)
Bibliography
http://www.nature.ca/genome/04/0413_e.cfm#010
<http://www.allupinyour.biz/wp-content/uploads/2008/07/mutation.jpg>
http://learn.genetics.utah.edu/archive/mutations/mutatedna.html%
20notes.htm