Unit A Flashcards
Definition of Dynamic Equilibrium?
Describes any system with constant change in which the components can adjust to the changes without disturbing the entire system
Definition of Biosphere?
The narrow zone around Earth that harbours life
Definition of Biotic Components?
The biological or living components of the Biosphere
Definition of Abiotic Components?
The non-living components of the biopshere. They include chemical and physical factors
Definition of Population?
A group of individuals of the same species occupying a given area at a certain time
Definition of Community?
The populations of all species that occupy a habitat
Definition of Ecosystem?
A community and its physical and chemical enviroment
Definition of Biodiversity?
The number of species in an ecosystem
Definition of Food Chain?
A sequence linking organisms that feed on each other, starting with a food source and continuing in order with each consumer
Definition of Producer
An Autotroph; an organism that makes its own food
Definition of Consumer?
A Heterotroph; an organism that must eat producers or other consumers to survive
Definition of Indicator Species?
A species sensitive to small changes in enviromental conditions
Definition of Herbivore?
An animal that eats only plants
Definiton of Carnivore?
An animal that feeds only on other animals
Definition of Omnivore?
An animal that eats both plants and other animals
Definition of Detritus?
Waste from plants and animals, inluding their dead remains
Definition of Decomposer?
An organism that feeds on detritus
Definition of Habitat?
A place or type of environment with conditions suitable for the survival of an organism or population of organisms
Definition of Ultraviolet Radiation?
Electromagnetic radiation from the Sun that can cause burning of the skin and other cellular mutations
Definition of Ozone?
An inorganic molecule. A layer of ozone found in the stratosphere helps to screen out UV Radiation
Definition of Trophic Level?
A category of living things defined by how it gains its energy; the first trophic level contains Autotrophs, and each higher levep contains Heterotrophs
Definition of Autotroph
An organism that uses the Sun’s energy and raw materials to make its own food; A producer
Definition of Primary Consumer?
In a food chain or food web, an organism that relies directly on autotrophs for its sourced of energy; organisms at the second trophic level
Definition of Secondary Consumer?
in a food
chain or food web, an organism that
relies on primary consumers for its
principal source of energy;
organisms at the third trophic level
Definition of Heterotroph?
an organism that is
incapable of making its own food, and so must feed on other organisms to gain energy
Definition of Food Web?
In this food chain, energy flows from a producer (the spruce tree), to a primary consumer (the deer), to a secondary consumer (the wolf).
Definition of Photosynthesis?
the process by which green plants and some other organisms use solar energy, carbon dioxide, and water to produce carbohydrates
Definition of Chemosynthesis?
the process by which non-photosynthetic organisms convert inorganic chemicals to organic compounds without solar energy
Definition of Chemoautotroph?
an organism that can synthesize organic compounds
from inorganic chemicals without using solar energy
Definition of Thermodynamics?
a scientific study of energy transformations, described
by laws
The 1st Law of Thermodynamics?
that although energy can be transformed (changed) from one form to another, it cannot be created or destroyed.
The 2nd Law of Thermodynamics?
during any energy transformation, some of the energy is converted into an unusable form, mostly thermal energy, which cannot be passed on. Each time energy is transformed, some energy is lost from the system.
Definition of Ecological Pyramid?
a representation of energy flow in food chains and webs
Defnition of Biomass?
the total dry mass of all
the living material in an ecosystem
Definitionof Monoculture?
cultivation of a single
species
Definition of Polar Molecule?
a molecule that has a positive and a negative end
Definition of Hydrogen Bond?
the type of bond that is formed between the positive end of one water molecule and the
negative end of another water
molecule
Definition of the Water Cycle?
the movement of water through the environment from the atmosphere to Earth and back
Definition of Transpiration?
the loss of water through plant leaves
Definition of Percolation?
the movement of a liquid through a porous material,
such as soil particles
Definiton of Water Table?
the top level of the region below the ground that is
saturated with water
Definition of Leaching?
the removal of soluble minerals by percolation
Definition of Carbon Cycle?
the cycle of matter in which carbon atoms move from an
inorganic form to an organic form and then back to an inorganic form
Definition of Combustion?
the chemical reaction that occurs when a substance reacts very quickly with oxygen to release energy
Definition of Peat?
slowly decomposing plant matter produced in low-oxygen
environments such as bogs
Definition of Albedo?
a term used to describe the
extent to which a surface can reflect light that strikes it. An albedo of 0.08 means that 8 % of the light is reflected.
Definition of Stromatolite?
a banded limestone structure containing fossilized
bacteria
Definition of Nitrogen Cycle?
a cycle of matter inwhich nitrogen atoms move from
nitrogen gas in the atmosphere, to inorganic forms in the soil, to organic forms in living things, and then back to inorganic forms in the soil and nitrogen gas in the atmosphere
Definition of Nitrogen Fixation?
two processes in which atmospheric or dissolved nitrogen is converted into nitrate ions
Definition of Denitrification?
the process in which nitrates are converted to nitrites and then to nitrogen gas
Definition of Fertilizer?
a material used to restore
nutrients to plants
Definition of Phosphorus Cycle?
The cycling of phosphorus between the biotic and abiotic components of the enviroment; consists of a biological and geochemical cycle
Definition of Nutrient?
a chemical that is essential
to living things
