Unit 2 Test Flashcards
Covalent Bonds
bonds formed between atoms by the sharing of elements - strong bond
Hydrogen Bonds
attraction between slightly positive hydration atom and slightly negative atom - weak bond
Polarity
the distribution of electrical charge over the atoms joined by the bond
Electronegativity
a chemical property that describes the tendency of an atom to attract electrons toward itself.
Hydrophilic substances
attracted to water, dissolves in water
Hydrophobic substances
repels from water (oily and greasy solutions)
Cohesion
attraction between molecules of the same substances
Adhesion
attraction between different substances
Homeostasis
A state of balance among all the body systems needed for the body to survive and function correctly
Solute
substance that dissolves in solvent
Solvent
able to dissolve other substances (water)
Solution
mixture composed of two or more substances.
Acid
a chemical substance that neutralizes alkalis, dissolves some metals, and turns litmus red
Base
any substance that in water solution is slippery to the touch, turns litmus blue
pH
measure of how acidic/basic water is
Hydrologic Cycle
water cycle
Condensation
the process where water vapor becomes liquid
Evaporation
the process of turning from liquid into vapor
Transpiration
the process by which plants give off water vapor through openings in their leaves
Precipitation
any liquid or frozen water that forms in the atmosphere and falls back to the Earth
surface runoff
water, from rain, snowmelt, or other sources, that flows over the land surface
Abiotic
non-living part of an ecosystem that shapes its environment
Biotic
a living organism that shapes its environment
Latitude
the measurement of distance north or south of the Equator
Topography
study of the land surface
Landmasses
a continent or other large body of land
Biodiversity
all the different kinds of life you’ll find in one area
biogeochemical cycles
The flow of chemical elements and compounds between living organisms and the physical environment
Habitat
a place where an organism makes its home
Ecological Niche
the role an organism plays in a community
Competitive Exclusion
the inevitable elimination from a habitat of one of two different species with identical needs for resources (gray squirrels replaced by red squirrels.)
Ecological Equivalent
species that use similar niches in different habitats or locations
Competition
organisms compete for the resources they need to survive, grow, and reproduce
Predation
the preying of one animal on others.
Mutualism
symbiosis that is beneficial to both organisms involved.
Symbiosis
any relationship or interaction between two dissimilar organisms
Commensalism
two organisms in which one benefits and the other derives neither benefit nor harm.
Parasitism
nonmutual relationship between two organisms in which one benefits at the expense of the other
Population Density
The number of individuals living within that specific location
Population Dispersion
describes the arrangement of individuals within a habitat at a particular point in time
Survivorship Curve
graphic representation of the number of individuals in a population that can be expected to survive to any specific age
Immigration
an animal establishes a home in a habitat because it has resources it can utilize or because the habitat is ideal for them
Emigration
an animal leaves its home because the habitat is no longer ideal for them and they need to find a more suitable environment
exponential growth
the unrestricted growth of a population of organisms, occurring when resources in its habitat are unlimited.
Logistic Growth
growth rate gets smaller and smaller as population size approaches a maximum imposed by limited resources in the environment
Carrying Capacity
a species’ average population size in a particular habitat.
Population Crash
a sudden decline in the numbers of individual members in a population, species or group of organisms
Limiting Factor
anything that constrains a population’s size and slows or stops it from growing
density-dependent limiting factors
disease, competition, and predation
density-independent limiting factors
pollutants in the environment, and climate extremes, natural disasyers
Succession
the process by which the structure of a biological community evolves over time
Primary Succession
development of an ecosystem that was not habituated before
Pioneer Species
the species that first colonize new habitats created by disturbance
secondary succession
growth of a damaged ecosystem that still has healthy soil
