Exam II - Chapter 5 Flashcards
Alters the product of the gene, and thus its function or activity
Type of mutation and location?
Substitution, insertion, deletion, duplication
Coding region
Alters the timing, location, or level of expression of the gene
Alters the developmental or environmental context in which the gene is expressed
Mutation located in CIS-REGULATORY REGIONS
Substitution, insertion, deletion, duplication that alters the binding affinity of promoters, activators, repressors, etc.
Alters the binding affinity and thus the activity of a promoter, activator, repressor, etc.
Type of mutation? Location of mutation?
Mutations to coding regions of trans-acting factor
Trans-regulatory regions
Alters where, when or to what extent inhibitory, activating, or other trans-acting regulatory factors are expressed
Type of mutation? Location of mutation?
Mutation to cis- or trans- regulatory regions of trans-acting factors
Trans-Regulatory Regions
Alters the timing, location, or level of expression of the gene
Alters the developmental or environmental context in which the gene is expressed
Located in Physiological Pathways (ex: hormones)
Type of mutation?
Mutations alter where, when, or how much an endocrine signal is produced
DNA sequences that resemble functional genes but have lost their protein-coding ability or are no longer expressed
Pseudogenes
“Fake genes”
Fossil genes
The process of receiving genetic material from an ancestor
Vertical gene transfer
Any process in which the genetic material is transferred to another organism without descent
Horizontal gene transfer
Humans exhibit _____ gene transfer.
Vertical
Bacteria exhibit _____ gene transfer.
Horizontal
(Ex: Use plasmids to go from one individual to another)
Mutations that affect cells in the body of an organism.
They affect all daughter cells produced by the affected cell and can affect the phenotype of the individual
*Not heritable*
Somatic mutations
In animals, somatic cells are/are not passed down to offspring.
Are NOT
Mutations that affect the gametes (eggs, sperm) of an individual and can be transmitted from parent to offspring.
Because they can be passed on, they create the heritable genetic variation that is relevant to evolution
Germ-line Mutations
Genetic makeup of an individual.
Specific alleles carried by an individual for any particualr gene
Genotype
An observable, measurable characteristic of an organism
Phenotype
Simultaneous occurrence of two or more discrete phenotypes within a population
Genetic polymorphism
A trait for which multiple, discrete phenotypes can arise from a single genotype depending on environmental circumstances
Polyphenic trait
A single base changes from one nucleotide to another
Point mutation (substitution)
A segment of DNA is inserted into the middle of an existing sequence. May be as short as a single base or as long as thousands of bases.
Insertion
A segment of DNA may be deleted accidentally. Small portion or entire set of genes may be removed
Deletion
A segment of DNA is copied a second time. Can happen to entire genes, even entire genomes
Duplication
A segment of DNA is flipped around and inserted backward into its original position
Inversion
Two chromosomes are joined together as one
Chromosome fusion
Chromosomes are duplicated or lost, leading to abnormal levels of ploidy
Aneuploidy
_____ mutation can be multiple base pairs at different locations
Point mutation
Example of chromosome fusion
Humans have 46 chromosomes. “Monkeys” have 48 chromosomes. What does this tell you?
This has happened recently (last 7 million years). After chimp lineage split from human lineage
Mutation that is subtle, minor, slight, almost undetected
Point mutation
Example of point mutation
6 fingers, finger fusion, skin pigmentation, enlarged skull
Point mutation has no _____, most are eliminated by _____.
No adaptation; by natural selection
3 Problems with evolution for the 1st 70 years
- Darwin knew nothing of mutations
- Darwin knew nothing about genetics
- Age of the Earth was not known
Germ-line mutations are _____.
Heritable
Ring-neck doves had only 3 colors for 800 years. Now, there are all kinds of colors and feather changes. Why?
We think inversions - chromosomes with tightly linked genes for dove color
Genes for dove color now slightly less linked
African violets are all sorts of colors, leaf types, etc. - this started occuring in the 1970’s. This is another example of…
Inversion
Evolution of complex eye seems to be due to….
Gene duplication
Ancestral opsin - red vs. green eventually created
Both green and red
Seeing both green and red provides tremendous amount of _____, advantageous.
Might help to determine if a fruit is _____ or not.
Selection; ripe
As our vision evolved more and more, we needed _____ less and less.
Our olfactory genes
_____% of all our olfactory receptor genes are fossilized
50%
Only 5 of 200 _____ are functional in humans, in contrast to rats with 160 of 200.
Olfactory genes
If the phenotype no longer provides _____, natural selection no longer eliminates harmful mutation and the gene _____.
An adaptation; fossilizes
Natural selection eliminates _____
Harmful mutations
What’s an example of a polyphenic trait?
Horns in beetles. Beetles that developed in an environment with ample nutrition attain a larger body size
*sensitive to environment*
