DNA, evolution, taxonomy Flashcards
What is the structure of DNA
A double helix, complimentary pairing of adjacent strands
What is DNA?
Deoxyribonucleicacid
What are the four bases in DNA and what is it connected to?
Adenine and Thymine, Guanine and Cytosine. It’s connected to the backbone of the DNA which is a sugar-phosphate backbone.
what is a mutation?
when there are changes in the expressions of a gene or chromosome that affects the proteins produced as a result
Natural Selection
also known as “survival of the fittest”. Organisms with genes more fit for the environment are more likely to survive and reproduce
Genetic Drift
changes in the genetic make-up of a smaller population due to unplanned coincidences
gene flow
Change in the population allele frequency due to migration
mate selection including how
the ability to let organisms pick their own mates to reproduce with through physical or behavioral traits
reproductive isolation
a way to keep 2 species isolated and apart
punctuated equillibrium
the theory that evolutionary change goes in short bursts rather than a steady constant path
homologous structures
organisms that share similar features or structures in their limbs but different functions
analogous structure
same function different structure
fossil record
a direct piece of evidence to show evolutionary change through time, adaptive radiations and extinction
gradual change
the theory that change goes at a steady and slow rate
embryology
the study of the development of organisms during the early stages of life
vestigial organ
organs/structures that lost its function/purpose over the course of evolution
fossil
the remains of an organism used as direct evidence for evolutionary change
who created the term natural selection and “survival of the fittest” and how
Charles Darwin. He used finches to study how they would adapt to different environments
biochemical relationships
organisms with more similar DNA and protein compositions are more likely to be related
3 domains and 6 kingdoms
domains: bacteria, eukarya, archaea
kingdoms: plantae, animalia, fungi, protista, eubacteria, aechaebacteria
vertebrates and invertebrates
vertebrates are organisms with back bones or spines, invertebrates are organism who don’t have them
prokaryotes
unicellular, no membrane bound organelles, no defined nucleus, very small, prokaryotic organelles with a flagellum lack the 9+2 pattern
eukaryotes
multicellular, has membrane bound organelles, has defined nucleus
evolutionary theory
the theory that all organisms evolve and diverge through a common ancestor
heterotrophs and autotrophs
heterotrophs consume food and find food. autotrophs make their own food
directional selection
overtime, the population switches from one extreme trait to the other
stabilizing selection
when no extreme traits are preferred and population stabilizes on the normal traits
disruptive selection
when both extreme traits are preferred. this can lead to divergence and adaptive radiation
adaptive radiation
adaptive radiation happens when a species rapidly diverges into multiple forms
speciation
speciation is when a species emerges into new/multiple species
convergence and ecological equivalents
convergence happens when two distinct species experience certain selection pressure, which causes the two species to evolve to have similar traits despite being isolated from each other
divergence
when one species diverges into two species
