Core Themes In The Study Of Life Flashcards
Adaptation
Inherited characteristic of an organism that enhances its survival and reproduction in a specific environment.
Adaptive radiation
Period of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles in their communities.
Allele
Any of the alternative versions of a gene that may produce distinguishable phenotypic effects.
Analogous
Having characteristics that are similar because of convergent evolution, not homology
Artificial Selection
The selective breeding of domesticated plants and animals to encourage the occurrence of desirable traits.
Biogeography
The study of the past and present geographic distribution of species.
Bioinformatics
The use of computers, software, and mathematical models to process and integrate biological information from large data sets.
Biology
The scientific study of life.
Biosphere
The fauna and flora together; all the living organisms at a location. The part of the Earth system comprising all ecosystems and living organisms, in the atmosphere, on land (terrestrial) or in the oceans (marine), including derived dead organic matter, such as litter, soil organic matter and oceanic detritus; the entire portion of Earth inhabited by life; the sum of all the planet’s ecosystems.
Bottleneck effect
Genetic drift that occurs when the size of a population is reduced, as by a natural disaster or human actions. Typically, the surviving population is no longer genetically representative of the original population.
Catastrophism
The principle that events in the past occurred suddenly and were caused by different mechanisms than those operating today.
Chromosome
A cellular structure carrying genetic material, found in the nucleus of eukaryotic cells – each of these consists of one very long DNA molecule and associated proteins. (In bacteria these usually consists of a single circular DNA molecule and associated proteins in the nucleoid region, which is not membrane-bounded).
Cline
A graded change in a character along a geographic axis
Community
All the organisms that inhabit a particular area; an assemblage of populations of different species living close enough together for potential interaction.
Convergent evolution
The evolution of similar features in independent evolutionary lineages.
DNA (deoxyribonucleic acid)
A double-stranded, helical nucleic acid molecule, consisting of nucleotide monomers with a deoxyribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and thymine (T); capable of being replicated and determining the inherited structure of a cell’s proteins.
Domain
1) A taxonomic category above the kingdom level. (2) A discrete structural and functional region of a protein.
Ecosystem
All the organisms in a given area as well as the abiotic factors with which they interact; one or more communities and the physical environment around them.
Emergent Properties
New properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases.
New properties that arise with each step upward in the hierarchy of life, owing to the arrangement and interactions of parts as complexity increases.
Endemic
Referring to a species that is confined to a specific geographic area.
Eukaryotic cell
A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles (e.g. protists have these type of cells).
Evolution
Descent with modification; the idea that living species are descendants of ancestral species that were different from the present-day ones; also defined more narrowly as the change in the genetic composition of a population from generation to generation.
Evolutionary tree
A branching diagram that reflects a hypothesis about evolutionary relationships among groups of organisms.
Family
In Linnaean classification, the taxonomic category above genus.
Founder effect
Genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of the original population.
Gene Expression
The process by which information encoded in DNA directs the synthesis of proteins or, in some cases, RNAs that are not translated into proteins and instead function as RNAs.
Gene flow
The transfer of alleles from one population to another, resulting from the movement of fertile individuals or their gametes.
Gene pool
The aggregate of all copies of every type of allele at all loci in every individual in a population. The term is also used in a more restricted sense as the aggregate of alleles for just one or a few loci in a population.
Genetics
The scientific study of heredity and hereditary variation
Genetic drift
A process in which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next; effects are most pronounced in small populations.
Genetic Variation
Differences among individuals in the composition of their genes or other DNA segments.
Genomics
The study of whole sets of genes and their interactions within a species, as well as genome comparisons between species.
Genus
A taxonomic category above the species level, designated by the first word of a species’ two-part scientific name.
Global Climate Change
Increase in temperature and change in weather patterns all around the planet, due mostly to increasing atmospheric CO2 levels from the burning of fossil fuels – the increase in temperature, called global warming, is a major aspect.
Hardy-Weinberg Principle
The principle that frequencies of alleles and genotypes in a population remain constant from generation to generation, provided that only Mendelian segregation and recombination of alleles are at work.
Homology
Similarity in characteristics resulting from a shared ancestry.
Homologous Structures
Structures in different species that are similar because of common ancestry.
Hypothesis
A testable explanation for a set of observations based on the available data and guided by inductive reasoning – is narrower in scope than a theory.
Kingdom
A taxonomic category, the second broadest after domain.
Micro evolution
Evolutionary change below the species level; change in the allele frequencies in a population over generations.
Mutation
A change in the nucleotide sequence of an organism’s DNA or in the DNA or RNA of a virus.
Natural selection
A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.
Negative feedback
A form of regulation in which accumulation of an end product of a process slows the process; in physiology, a primary mechanism of homeostasis, whereby a change in a variable triggers a response that counteracts the initial change.
Organismal ecology
The branch of ecology concerned with the morphological, physiological, and behavioural ways in which individual organisms meet the challenges posed by their biotic and abiotic environments.
Palaeontology
The scientific study of fossils.