Studied by 50 people
Interspecific
occurring between different species.
Community
Population of different species.
Ecological Niche
A particular area within a habitat occupied by an organism, as well as the function of that organism within its ecological community.
Physical Environment
non-living aspects of our surroundings that affect living organisms and ecosystems
Symbiosis
any type of close and long-term biological interaction between two different biological organisms of the same or different species
Amensalism
The interaction between two species whereby one species suffers and the other species is not affected.
Commensalism
The interaction between two species whereby one organism benefits and the other species is not affected.
Competition
Interaction between organisms when they share limited resources in an ecosystem
Intraspecific
Competition between members of the same species.
Mutualism
The interaction between two species whereby both species benefit.
Parasitism
The interaction between two species whereby one species is benefited, and the other species is harmed.
Specialist predators
organisms that are highly adept at hunting and consuming a specific prey species, or even just a specific life stage of that species.
Law of Tolerance
the existence, abundance, and distribution of species depend on the tolerance level of each species to both physical and chemical factors.
Limiting Factor
Any abiotic factor that limits or prevents the growth of a population.
Spatial Partitioning
When competing species use the same resource by occupying different areas or habitats within the range of occurrence of the resource
Temporal Partitioning
When two species eliminate direct competition by utilizing the same resource at different times
Deserts
A region characterized by extremely low precipitation
Arctic tundra
characterized by extremely cold temperatures, short growing seasons, permafrost, and treeless plains
Aestivation
summer hibernation
Forests
Covers about one-third of Earth's land surface and accounts for 75% of gross primary productivity and plant biomass.
Tropical Rainforests
Lush, evergreen forests found in warm, humid regions near the equator, characterized by tall trees, abundant rainfall, and incredible biodiversity.
Temperate Deciduous Forests
Vibrant ecosystems found in mid-latitude regions around the world, and characterized by distinct seasonal changes, with green foliage in spring and summer and display of colors and leaf loss in autumn.
Taiga
Largest terrestrial biome; found in northern Eurasia, North America, Scandinavia, and two-thirds of Siberia.
Savannas
Grasslands with scattered individual trees and cover almost half the surface of Africa and large areas of Australia, South America, and India.
Temperate Grasslands
Environment where grasses are the dominant vegetation, while trees and large shrubs are absent.
Tundra
Environment that has extremely low temperatures, low biotic diversity, and simple vegetation structure.
Permafrost
Layer of permanently frozen subsoil.
Krill
Key food source in arctic ecosystems and serves as food for many predators.
Photic Zone
The layer just above the depth where the rate of carbon dioxide uptake by plants is equal to the rate of carbon dioxide production by animals.
Barrier reefs
Reefs that grow parallel to the coastline and are separated by deeper, wider lagoons. At their shallowest point, they can reach the water’s surface, forming a “barrier” to navigation.
Littoral Zone
Ecological zone found in coastal environments where land and water meet
Profundal Zone
Deepest layer of freshwater ecosystems that lies below the photic zone (where sunlight penetrates) and is characterized by cold temperatures, darkness, and low oxygen levels.
Stratification
Formation of distinct layers within a body of water with varying densities due to differences in temperature and salinity
Wetlands
Areas that are covered with water at some point in the year and that support aquatic plants.
Carbon
fundamental element exchanged among the biosphere, geosphere, hydrosphere, and atmosphere and is the basic building block of life and found in carbohydrates, fats, proteins, and nucleic acids.
Ocean Acidification
The ongoing decrease in the pH of the Earth's oceans, disrupting the creation of coral reefs and the viability of externally fertilized egg cells; Occurs when atmospheric carbon dioxide reacts with seawater to form carbonic acid,
Nitrogen
Element that takes up 78% of the atmosphere. Needed for photosynthesis
Nitrogen Cycle
A biogeochemical process through which nitrogen is converted into many forms, consecutively passing from the atmosphere to the soil to organism and back into the atmosphere
Nitrogen Fixation
When atmospheric nitrogen is converted into ammonia (NH3) or nitrate ions (NO3–), which are biologically usable forms of nitrogen.
Natural Cycling of Nitrogen
Atmospheric nitrogen is converted to nitrogen oxides by lightning and deposited in the soil by rain, where it is assimilated by plants and either eaten by animals or decomposed back to elemental nitrogen by bacteria
Nitrification
When ammonia (NH3) is converted to nitrite (NO2–) and nitrate (NO3–), which are the most useful forms of nitrogen to plants.
Assimilation
When plants absorb ammonia (NH3), ammonium ions (NH4+), and nitrate ions (NO3–) through their roots.
Ammonification
When decomposing bacteria convert dead organisms and wastes, which include nitrates, uric acid, proteins, and nucleic acids, to ammonia (NH3) and ammonium ions (NH4+)—biologically useful forms.
Denitrification
When anaerobic bacteria convert ammonia into nitrites (NO2–), nitrates (NO3–), nitrogen gas (N2), and nitrous oxide (N2O) to continue the cycle.
Nitrous oxide (N2O)
A greenhouse gas breaks down and destroys atmospheric ozone in the stratosphere.
Phosphorus
Element essential for the production of nucleotides, ATP, fats in cell membranes, bones, teeth, and shells.
Water cycle
the continuous movement of water on, above, and below the surface of the Earth
Condensation
The conversion of a vapor or gas to a liquid
Evaporation
The process of turning from a liquid into vapor
Evapotranspiration
The process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants
Infiltration
The process by which water on the ground surface enters the soil
Runoff
Part of the water cycle that flows over land as surface water instead of being absorbed into groundwater or evaporating
Capillary Action
A result of hydrogen bonding, helps tree roots take up water, allowing trees to grow as large as they do.
Photosynthesis
When plants remove carbon dioxide from the atmosphere and use light energy to produce carbohydrates and other organic compounds
Trophic Level
The position an organism occupies in a food chain; the number of steps it takes from the chain's start.
Food web
The natural interconnection of food chains.
Second Law of Thermodynamics
States that as energy is transferred or transformed, more and more of it is wasted.
Heterotrophs
Organisms dependent on photosynthetic organisms.
Cellular Respiration
the process by which organisms break down glucose and other organic molecules to release energy
10% Rule
States that energy is lost mostly as heat from one stage to the next.
Productivity
The rate of generation of biomass in an ecosystem (mass per unit surface area (or volume) per unit time)
Biomass pyramid
Shows how much organic mass is within each trophic level.
Gross primary production (GPP)
The rate at which plants capture and fix a given amount of chemical energy as biomass in a given length of time.
Net primary production (NPP)
The remaining fixed energy is the rate at which all the plants in an ecosystem produce net useful chemical energy.
Genetic Diversity
The range of all genetic traits, both expressed and recessive, that make up the gene pool for a particular species
Species Diversity
Number of different species that inhabit a specific area
Population Bottleneck
Large reduction in the size of a single population due to a catastrophic environmental event
Generalist Species
Species that live in different types of environments and have varied diets
Specialist Species
Species that require unique resources and often have a very limited diet
Species Richness
The number of different species (diversity) represented in an ecological community or region
Theory of Island Biogeography
Proposes that the number of species found on an "island" is determined by immigration and extinction of isolated populations
Pioneer Species
Earlier successional plants, generalists
r-Strategists
Mature rapidly; short-lived species; number of organisms within a species is high; low biodiversity; niche generalists
K-Strategists
Mature slowly; long-lived; number of organisms within a species is lower; greater biodiversity; niche specialists
Ecological succession
The process of change in the species structure of an ecological community over time, which can be millions of years in the case of primary succession or decades in the case of secondary succession
Primary succession
The evolution of a biological communitys ecological structure in which plants and animals first colonize a barren, lifeless habitat
Secondary succession
A type of ecological succession in which plants and animals recolonize a habitat after a major disturbance
Keystone species
A species whose presence contributes to a diversity of life and whose extinction would lead to the extinction of other forms of life
Indicator Species
Organisms whose presence, absence, or abundance reflects a specific environmental condition and can indicate the health of an ecosystem
early stages of succession
Stage in succession when gross productivity is low due to the initial environmental conditions and low numbers of producers.
Carrying capacity (K)
Refers to the number of individuals that can be supported sustainably in a given area
Population Dispersal Pattern
How individuals or species of animal become distributed in different spaces over certain periods
Biotic potential
The maximum reproductive capacity of an organism under optimum environmental conditions
Environmental Resistance
Any factor that inhibits an increase in the number of organisms in the population
J-Curve
A curve that represents population growth occurs in a new environment when the population density of an organism increases rapidly in an exponential or logarithmic form, but then stops abruptly as environmental resistance or another factor suddenly impacts the population growth
S-Curve
A curve that represents when, in a new environment, the population density of an organism initially increases slowly but then stabilizes due to the finite amount of resources available
Density-dependent limiting factors
Factors whose effects on the size or growth of the population vary with the density of the population
Density-independent factors
Factors that limit the size of a population, and their effects are not dependent on the number of individuals in the population
Doubling time
Amount of time it takes for a population to double in size [70/% growth rate]
Birth Rate (%)
[(total births/total population)] × 100
Crude Birth Rate (CBR)
[(b ÷ p) × 1,000]
Death Rate (%)
[(total deaths/total population)]× 100
Crude Death Rate (CDR)
[(d ÷ p) × 1,000]
Emigration
number leaving a population
Global Population Growth Rate (%)
[(CBR – CDR)]/10
Immigration
number entering a population
National Population Growth Rate (&)
[(CBR + immigration) – (CDR + emigration)]/10
Percent Rate of Change
[(new # - old #)/old #] × 100
Population Density
Total population size/total area
Population Growth Rate (%)
[(births + immigration) - (deaths + emigration)]/total population
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Flashcard (22)