Download What are mutations and how do they affect the production

Name: __________________________________
Aim 25: What are mutations and how do they affect the production of proteins?
What is a
Mutation?
What does a
mutation
cause?
Date: ________________
A _____________________ or random change in the genetic material (DNA sequence) of an organism.
When the base sequence of DNA is __________________, the ______________________ sequence is
also changed. Since amino acids chain together to create a specific ____________________, mutations
could affect the operation of an ____________________, preventing it from properly catalyzing a reaction
or preventing a ________________ from being ____________________ by the cell
When do
mutations
occur?
The enzymes responsible for matching up the nucleotide bases can match the ______________ bases
together, ___________ a base out, or __________ an extra base. This occurs during DNA
______________
What can
cause
mutations?
The rate of mutations can be increased by exposure to ___________________________ or
__________________________, which are ________________________ factors that can cause a
mutation.
Examples:
What types of mutations are there?
Substitution
Insertion
_______________ of one base for another.
_________________ of an extra base into an
existing DNA sequence.
Deletion
A base is _____________________ from the
normal DNA sequence.
Inversion
Bases within the gene (DNA segment) are
__________________ or flipped
Chromosome
Mutation
•
Person inherits _________________ or ______________ chromosomes.
•
Often _______________ (cause death)
*EXCEPTION: _______________________________________
•
Non-lethal
•
Inheritance of an ___________chromosome on chromosome #______
(all human cells have 46 chromosomes. Someone with Down’s has _____ chromosomes)
If a change (mutation) occurs in the original DNA sequence this COULD cause a change in the amino
acid sequence and therefore change the shape and function of the protein that is produced.
Does a
mutation
ALWAYS
cause a change
in the
protein’s
shape and
function?
Example 1: mRNA strand: UCGCACGGU
AA seq: ____________________________________
Mutated mRNA strand: UCGUACGGU
AA seq: ____________________________________
•
Will this change the protein’s shape? _______ Will this change the protein’s function? _______
------------------------------------------------------------------------------------------------------------------------------Example 2: mRNA strand: AUGGUAACAAAG AA seq: __________________________________
Mutated mRNA strand: AUGGUAACCAAG AA seq: __________________________________
•
Will this change the protein’s shape? _______ Will this change the protein’s function? _______
•
This is what is called a ________________ mutation because the change in the DNA sequence
______________ change the protein and therefore will have NO EFFECT on the organism
What is the
difference
between a
“good” and
“bad”
mutation?
1. BAD MUTATIONS: Can cause an organism to no longer _______________________ properly.
Could result in _________________________ of
organisms. (Ex: ____________________ cell
division can lead to __________________
2. GOOD MUTATIONS: Provide for a source of __________________________that may make an
organism ________________ for its environment (increases chances of survival)
•
Sexually reproducing organisms have sex cells or _______________________ (eggs in ovaries and
sperm in testes ONLY) and non sex cells or _____________________ (all other body cells:
Can mutations
be passed onto
offspring?
muscle, liver, skin cells etc).
•
MUTATIONS CAN ONLY BE INHERITED (passed onto offspring) if they occur in the
organism’s ___________________ (egg or sperm cells)
•
Body cells that have a mutation WILL pass that mutation to every ____________ that develops
from it through cell division. Their offspring _______________ inherit this mutation.
Mutation Practice Questions