ENVIRONMENTAL SCIENCE PRELIM FLASHCARDS SET 2 (26–50)

octet rule

To help predict which atoms are likely to form covalent bonds, scientists use the octet rule.

work

form of energy that only exists when energy is being transferred between the surrounding environment and a system.

energy

ability of matter to move from one place to another or from one state to another.

reinforcing feedback

a positive feedback which sends the system farther from stability.

stabilizing feedback

negative feedback which helps the system return to a steadier state.

medical properties of water

Acting as solvent; Creating surface tension; Moving upward with capillary action; The unbearable lightness of ice.

cation

positive ion.

anion

negative ion.

nucleus

(or center) of an atom is composed of subatomic particles called protons and neutrons.

neutron

have a neutral or zero charge.

cellulose

an example of complex carbohydrates which forms structures such as plant fibers.

disphotic zone

Deeper waters in the pelagic zone (below 200 meters) are part of the bathyal zone, which receives less sunlight than the euphotic zone above it and is sometimes called the disphotic zone.

hydrologic cycle

has no beginning or end (hence the term cycle), you can jump in at any stage; doesn't occur in a straight line.

water

is quite possibly the most important resource the environment provides. All living things need water in order to survive.

carbon cycle

Green plants use the CO₂ during photosynthesis to create sugars that provide energy for living organisms. In this way, carbon moves from the atmosphere to plants and animals.

phosphorus cycle

living organisms use the element phosphorus to build nucleic acids (such as DNA) and other important organic molecules used by cells in living processes.

sulfur cycle

similar to phosphorus, sulfur is stored in rocks. Erosion and volcanic activity naturally release sulfur into the surface environment.

nitrogen cycle

during the cycle, nitrogen may transfer between the living and non living parts of the environment with the help of nitrogen-fixing bacteria and denitrifying bacteria.

nutrient cycle

carbon cycle; nitrogen cycle; phosphorus cycle; sulfur cycle.

energy pyramid

shows how the energy in an ecosystem is distributed among the trophic levels (in joules, J).

consumption

One way matter and energy move around in an ecosystem is through consumption, or eating.

gross primary productivity

The total energy captured by producers.

net primary productivity

the gross primary productivity minus the energy used for producers' respiration.

biomass pyramid

similar to an energy pyramid; the distribution of biomass, or biological matter, in an ecosystem. Like energy, the total amount of organic matter decreases as it moves up through the trophic levels.

carrying capacity

is the number of individuals that the available resources of an environment can successfully support.

individual

a simplest level; a member of a population.

population

is made up of a group of individuals of the same species that occupy the same environment and interact with each other.

limiting resource

is a resource that organisms must have in order to survive and that is available only in limited quantity in their environment.