Evolution Flashcards
What is genomics?
the study of an entire organism’s genome
What is a genome?
the whole set of an organism’s genes
What is bioinformatics?
the study of the information in life (DNA)
What was the Human Genome Project and what was its purpose?
genome organized from 1990-2003
- relativeness between species
- ancestory
What is DNA sequencing?
determining the sequence of nucleotides (base pairs)
What is Darwin’s book and what were his two pillars in it?
On the Origin of Species by means of natural selection
- descent with modification from a common ancestor (macroevolution)
- natural selection is the mechanism for this (microevolution)
What is microevolution?
changes in allele frequencies in a population over time
What are allele frequencies?
how many times an allele appears in a population
What is an allele?
gene pair
Who developed the theory of use and disuse and what does it say?
parent giraffes stretched their neck out to reach the leaves then passes on stretched out neck to offspring but this is an acquired trait
Lamarck
What is natural selection?
process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits
What are the 2 exceptions of natural selection/
- cannot create anything new, selects existing traits
- does not occur in individuals, only populations
What are 4 sources of individual genetic variation?
- mutations- point mutations
- changes in gene location- duplications, inversions, and translocations
- rapid reproduction in prokaryotes- resistance to antibiotics
- random fertilization in eukaryotes- also gamete formation/crossing over and independent assortment
What is a population?
a group of individuals of the same species that live in the same area, interbreed, and produce fertile offspring
3 types of changes in allelic frequencies
- natural selection- drought, color of habitat, color of organisms attracting predators
- genetic drift- random chance event cause a change in frequencies, lava, smaller population=more deviation
- gene flow- transfer of alleles between populations, animals migrating in and out of population (beetles and log)
artificial breeding
selective breeding for specific traits
hybrid
offspring resulting from two different varieties of the same species, have hybrid vigor- fewer problems than purebred
gene pool
the sum of all the alleles that all the members of a species can possess
Hardy-Weinburg principle
used to determine if a population is evolving, the allele frequencies and the ratio of heterozygous to homozygous individuals in a given population will remain constant unless the population is affected by factors outside the original population
Conditions for genetic equilibrium
- large population (no genetic drift)
- population must be isolated from others (no gene flow)
- random mating (no preference for certain phenotype)
- no mutations
- all individuals have equal chance to survive and reproduce (no natural selection)
What is the Hardy-Weinburg equation? What do the p and q represent? Which of the variables would be easiest to find first?
p (squared) + 2pq + q (squared) = 1
p = frequency of dominant trait or allele
q = frequency of recessive trait or allele
recessive because of different phenotype
2 types of genetic drift
- founder effect- few individuals break off and become isolated from a large population (Pilgrims)
- bottleneck effect- sudden reduction in population size due to a change in the environment
Limits of natural selection
- only act on existing variation (no new genetic information)
- historical constraints (can’t go back and change history)
- adaptions are mostly compromises (might not be beneficial - frog vocals that attract mates but also attract bates)
- chance, natural selection, and the environment interact
7 levels of classification
Kingdom, Phylum, Class, Order, Family, Genus, Species (means “kind” - Genesis account)
speciation
rise of species (not defined by appearance - black and white people are of the same species)
What are the 2 types of speciation?
- allopatric speciation- other country - population becomes divided geographically which lead to 2 new species
- sympatric speciation- same country - new species without being separated (food source or same color)
What is the biological species concept?
groups of populations whose members can interbreed that produce viable and fertile offspring
What is reproduction isolation?
biological factors that prevent 2 species from being able to produce fertile offspring
What are the 2 types of reproductive isolation?
Pre and post-zygotic barriers
Prezygotic barriers
- behavioral isolation (different ways of mating dances, calls, and nests)
- temporal isolation (skunks- Montana and Louisiana: different mating seasons)
- gametic isolation (sperm can’t penetrate the egg- aquatic animals and pollen of maple and pine tree)
- habitat isolation (living in different regions)
- mechanical isolation (reproductive parts don’t fit)
Postzygotic barriers
- offspring don’t survive
- offspring can survive but are sterile (horse + donkey = mule)
- offspring survive and reproduce but 2nd generation is sterile
