Unit 3 Molecular Genetics Lesson 7 6.0-11.0 Flashcards
What are large scale mutations?
Mutations that involve multiple nucleotides, entire genes or whole regions of chromosomes.
What effects can large scale mutations have?
Various ones
When does amplification occur in large scale mutations?
when a gene or group of genes is copied to multiple regions of chromosomes
What do large scale mutations lead to?
a larger number of copies of the gene which compounds its effect
What do large scale deletions remove?
entire coding regions of the DNA (muscular dystrophy)
What is translocation?
A process that occurs when entire genes or groups of genes are moved from one chromosome to another
What happens if a DNA coding sequence is translocated adjacent to another coding sequence?
this can result in an entirely new gene and a completely novel polypeptide chain
When does inversion occur?
when a portion of a DNA molecule often containing one or many genes reverses its direction in the genome
What is a trinucleotide?
a triplet of nucleotides
What is a normal trinucleotide?
CAG, CAG, CAG, CAG
What is Huntington’s disease caused by?
An expansive trinucleotide repeat
What are two types of mutation causes?
Spontaneous
Induced
What are spontaneous-caused mutations?
arise from inaccurate DNA replication
What are induced-caused mutations?
caused by an environmental agent known as a mutagen
What are examples of mutagens?
Chemicals, Radiation
What are considered chemicals?
Any chemical agents that can enter a cell and chemically alter the structure of the DNA.
What are examples of mutagens? What are they linked to?
CO and tobacco smoke act as mutagens and are linked to various forms of cancer
Nitrous acid can
What can Nitrous Acid do?
modify individual nucleotides so that the nucleotides resemble other base pairs (confuses the replication machinery)
What do benzene molecules do?
cause mutations by mimicking a DNA nucleotide (change of shape)
What does radiation involve?
Electromagnetic, low energy, and high energy radiation
How does radiation affect mutations?
Breaks bonds of the DNA interfering with replication
What do beneficial (positive) mutations result in?
greater survival and reproductive success
What do neutral mutations result in?
They are the majority of mutations
They are silent
What is the duration of mutations?
They can act for a small amount of time or a long amount of time depending on the gene or protein they effect.
What are detrimental (negative) mutations?
Lesser survival and reproductive success
