Evolution Flashcards
What can selective pressure lead to?
Genetic changes (sometimes punctuated equilibrium)
What is hybridization?
Process of an animal/plant breeding with another species
What is a theory?
A well-supported explanation of the natural world based upon observation and experimentation
How do hypotheses work?
They have a base, and experiments are made to disprove them. If they can’t be disproven, they turn into theories
What are theories used for?
Explain known phenomena and predict new events
What has to be done if a theory no longer functions to explain known phenomena?
It needs to be changed or modified
What is a population?
A group of organisms of the same species
What is a species?
A group of organisms that are capable of interbreeding (with exceptions)
What are some examples of exceptions to the definition of a species?
Baltimore Oriole and Bullocks Oriole
What is fitness?
A measure of an organism’s ability to survive and reproduce in an environment
What is a way we measure evolution?
Fitness
Evolution doesn’t always lead to…
Speciation
What is a genetic drift?
A change in the frequency of a gene within a population due to mutation
What is a genetic flow?
A change in the frequency of a gene within a population due to migration
What is an example of genetic flow?
Fox squirrels
What is pre-zygotic isolation?
When sperm can’t fertilize the egg
What is post-zygotic isolation?
When hybrid species are made, but they’re sterile (can’t reproduce)
What is a cline?
A gradual change of a character or feature in a species over a geographical area
What does cline lead to?
Speciation
What is allopatric speciation?
Occurs when 2 populations are living in separate environments and therefore there is no gene flow. They will differentiate to the point where they are distinct species
What is sympatric speciation?
When 2 members of a species become reproductively isolated and diverge without physical separation
What is natural selection?
Process when favorable traits become more common and unfavorable traits become less common
What is inter specific competition?
Competition between individuals of different species
What is intraspecific competition?
Competition between individuals of same species
What are the 4 elements that evolution by natural selection can be thought of?
Variation, Inheritance, Selection, and Time
What causes variation?
Mutations, sexual reproduction, and migration
What are mutations caused by?
Random changes in the DNA
Are mutations considered good or bad most of the time?
Bad because they usually hinder an organism’s chances at survival
What happens during sexual reproduction?
Existing DNA is rearranged
What happens during migration?
Genes entering or leaving a population
How does inheritance happen?
Traits are passed down from parents to offspring
What is punctuated equilibrium?
Populations show little change for most of their geological history, but when phenotype evolution does occur, it is in rare and rapid events of branching speciation
Individuals that are best suited for the environment will…
Survive and reproduce more
What does punctuated equilibrium lead to?
Branching speciation (cladogenesis)
What is an allele?
One or two or more alternative forms of a gene that arise by mutation
Speciation is the result of _________, but evolution doesn’t always result in __________
Evolution, speciation
What are antibiotics?
Drugs that inhibit or abolish the growth of micro-organisms such as bacteria, fungi, or protozoans
What was the term antibiotic originally used to refer to?
Any agent with biological activity against living organisms
What is the term antibiotic used to refer to now?
Substances with anti-bacterial, anti-fungi, or anti-parasitical activity
What causes death of living tissue?
Anthrax
What are some misuses of antibiotics?
Incomplete treatment and over-prescribing antibiotics, especially for viral infections
Antibiotic resistance may be due to things like…
Increasing use of antibacterial soap
What do viruses spread by?
Arisols
What is science?
The body of knowledge that exists about the world and the method used to obtain that knowledge
What is a phenomenon?
A fact, occurrence, or circumstance observed
What is data?
Facts and observations gathered and recorded about a problem
What is an experiment?
An organized, purposeful test in which certain conditions are changed