Chapter 14 Flashcards
A chemical agent that interferes with DNA repair may be considered a mutagen.
True
Definition of polymorphism
Any genetic difference among individuals that is present in multiple individuals in a population.
What are the types of chromosomal alterations
deletion
duplication
inversion
translocation
Copy number variation
the genetic trait involving the number of copies of a particular gene present in the genome of an individual
What is SNP
is a variation at a single position in a DNA sequence among individuals
What is an example of a gene family
hemoglobin
What is differential gene expression with respect to hemoglobin
Adults have less tightly oxygen binding
Fetus has tightly oxygen binding to get oxygen into the placenta
Genome sequences are used to establish ___________ ______________
evolutionary relationships
There is little relationship between size and number to complexity of organisms
True
What are two examples of the relationship between organisms and complexity
Protein Complexes
Protome is Large (alternative splicing)
Silent Mutations
Do not affect protein function (phenotypic effect)
Loss of Function mutation
codes for nonfunctional proteins (phenotypic effect)
Gain of function mutation
codes for a protein with new function (phenotypic effect)
Conditional mutation
Seen under restrictive conditions but not permissive conditions (phenotypic effect)
Point Mutations
change in single base pair (loss, gain, or substitution)
Chromosomal Mutation
Change in segments of DNA (loss, duplication, rearrangment)
Single base pair mutation
Not seen in proofread
Silent Mutations (synonymous)
change one nucleotide (wobble cause no effect) no change/slight change (point mutation)
Missense Mutation
base substitution results in amino acid substitution
defective proteins, altered proteins, no effect
(Sickle-Cell) (point mutation)
Nonsense Mutation
stop codon introduced early
almost always harmful
(point mutation)
Frame-Shift Mutation
bases inserted or deleted
(point mutation)
4 types of chromosomal mutations
Deletions - loss of chromosomal segment
Duplication - repeat of chromosomal segment
Inversion - breaking and rejoining of a segment “flipped”
Translocation - segment of DNA breaks off and inserted into another chromosome
Wild-type sequence
most common DNA sequence in the population
DNA damage from
spontaneous DNA decay
environmental mutagen
Mismatch Repair
mismatched bases (have template strand that is undamaged to repair the damaged strand)
Base Excision Repair
Scan DNA for damaged or improper bases (change one base)
Nucleotide Excision Repair
Change many nucleotides
Mutations are ___________. Example? Unconnected to an organism ______
Random
Yield antibiotic resistant
needs
Mutation per genome per generation. These mutations account for ________ _________ of populations and the __________ of individuals
genetic diversity, uniqueness
How are VNTRs used in fingerprinting?
Variable nucleotide tandem repeats
Short nucleotide sequences that vary in number between individuals
EX: Paternity Test
What is an SNP and how does it affect eye color?
Single nucleotide polymorphism
occur when a single nucleotide is replaced with another
too common to be a mutation
What is copy number variation and how is it genotyped?
Differences among individuals in the number of copies of a region of the genome
What is trisomic? Monosomic?
1 extra chromosome
1 less chromosome
What is nondisjunction?
causes an abnormal number of chromosomes in all the cells
What is aneuploidy
the condition of having an abnormal number of chromosomes in a haploid set
What is a triploid?
Polyploidy?
Tetraploid?
an additional set of chromosomes
more than two complete sets of chromosomes
containing four homologous sets of chromosomes
An individual has an extra chromosome 21. What genetic condition is this?
Down Syndrone
What is the difference between trisomy and triploid?
trisomy - 1 extra chromosome
triploid - 1 extra set of chromosomes
What is a karyotype? What is it used for?
Visual image of chromosomes in a cell of an organism. Used to examine chromosomes to identify abnormalities to diagnose different diseases or conditions
translocation
a piece of one chromosome breaks off and attaches to another chromosome
inversion
- a segment of the chromosome breaks off and reattaches in the reverse direction
duplication
one or more copies of a DNA segment is produced
deletion
the absence of a segment of DNA
What are the four point mutations?
Silent Mutations
Missense Mutation
Nonsense Mutation
Frame-Shift Mutation
