Download Notes Unit 4 Part 8

BIOLOGY NOTES
GENETICS PART 8
PAGES 252-285
NAME:
DAY / MOD:
DATE:
Standards:
____ Explain how mutations in DNA sequences may or may not result in phenotypic change. Explain how
mutations in gametes may result in phenotypic changes of offspring.
____ Evaluate the impact of biotechnology on the individual, society, and the environment, including medical
and ethical issues
____ Describe how mutation and genetic recombination increase genetic variation
Essential Questions:
1.
2.
3.
I. Mutations
Mutation = a change in an organism’s ________
 mutations are ____________ and can have unpredictable effects
 errors in DNA provide the ______________ that is fundamental to the evolution of a species
 most mutations result in ___________ or the lack of normal development in an organism
 if the mutation occurs in ____________, birth defects can occur
 if the mutation occurs in ____________, cancer may occur
 mutagens = factors in the _______________ that cause mutations to occur
e.g.
 carcinogen = mutagens that specifically cause _________
e.g.
Types of Mutations:
A. Gene Mutation = mutations that involve a change in the sequence of _______________ within a
___________ gene
 occur most often during ______ replication so affect _____________ cells more often
 phenotype may or may ______ be altered depending on type of mutation
Types of Gene Mutations:
1. point mutation = a gene mutation involving changes in ____ or few nucleotides
 usually only ______ amino acid is effected
a. substitution - a mutation in which one base is ______________ for another
2. frameshift mutation = a gene mutation in which the “reading _________” of the genetic message is
_____________
 changes the __________ amino acid sequence
 drastically changes the __________ so that it is unable to perform its normal _____________
a. insertion - a nucleotide is ____________ to the genetic code
b. deletion - a nucleotide is ____________ from the genetic code
B. Chromosomal Mutation = mutations involved in changing the ____________ or ___________ of
chromosomes
 chromosomal mutations occur in all organisms but most often in __________
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
usually occur because parts of ____________ are broken off or lost during _____________ when
homologous chromosomes pair together so affect ____________ cells more often
phenotype almost always _________________ since mutation involves a large number of ________ being
affected
 non-disjunction = the failure of ____________ chromosomes to separate properly during meiosis
e.g.

Types of Chromosomal Mutations:
a. Insertion – part of a _____________ breaks off and attaches to its sister chromatid
DIAGRAM:
b. Deletion – part of a _____________ is left out
DIAGRAM:
c. Inversion – part of a _________________ breaks out and is reinserted backwards
DIAGRAM:
d. Translocation – part of one _____________ breaks off and is added to a different chromosome
DIAGRAM:
II. Manipulating DNA & Biotechnology
A. Cutting DNA
 Scientists can extract ______ from cells, cut it into small pieces, and individually study each piece
 Restriction enzymes = enzymes that cut ______ at a specific sequence of ________________
 using restrictive enzymes allows scientists to read much __________ pieces of DNA at a time
 restriction enzymes are used by _______________ to defend against _____________
e.g.
B. Organizing DNA
 Gel Electrophoresis = using electric ____________ applied to a gel mixture of ____ fragments in
order to separate the DNA fragments based on their molecular ________
 can be used to compare genomes of different organisms by using restriction _________
 genome = an organism’s complete set of ______ within a cell
 can also be used to compare the gene sequences of organisms of the same species

when used with _________ or a polymerase chain reaction, gel electrophoresis can be used as a type of
DNA ______________ in crime labs to identify suspects. This is much more precise than simple
________ testing because the DNA of every __________ is different
III. Genetic Engineering = making changes in the _____ code of living organisms
Scientists today can use their knowledge of genetics in order to study and __________ the DNA within
living organisms. Genetic engineering is useful because the genetic code is ______________!!!
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A. How Can DNA Be Changed?
 Cloning = creating a genetically identical copy of a _______ or of an organism
 first successfully cloned mammal was a sheep named _________ in 1997
 does not necessarily mean the outcome will be _________________ due to environmental influences
that could affect _________ expression
 useful in cloning organs for ____________ or possibly saving an endangered ____________

Recombinant DNA = DNA produced by combining the ________ from many different ____________
 Genes responsible for producing specific _______________ can be extracted from an organism using
____________________ enzymes
 These genes can then be spliced into a plasmid
 plasmid = a small circular piece of _______ found naturally in some bacteria
B. How Can Changed DNA (Recombinant DNA) Be Used?
Once the foreign DNA is _________________ into the plasmid, the plasmid is returned to the bacteria
 transgenic = referring to organisms that contain __________ from a different organism within its
genome
 If the plasmid is accepted, the foreign DNA will be replicated very fast as the bacteria multiply
 having lots of specific genes allows for those gene’s products to be _________________ as well
 transformed = referring to organisms containing foreign ______ that express the products of the new
___________
e.g.


Sometimes the treated bacteria can be used to introduce the recombinant plasmid into ____________ cells
or ______________ cells
 often, these plants and animals are referred to as GM or __________________
_________________
e.g.

Since the genetic code is ___________________, recombinant DNA can also be used to cross genes
among different ___________________
e.g.
STUDENT SYNTHESIS
To demonstrate knowledge of the information contained within these notes, within the space below EITHER 1. Create two higher
level test questions and answers based on the information OR 2. Write a comprehensive summary of the information
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