AP/IB Semester Exam Review Set

MEDCs

More Economically Developed Countries, such as the United States.

LEDCs

Less Economically Developed Countries, such as those in Africa.

Tragedy of the Commons

The depletion of shared resources by groups or individuals despite knowing it is not in their long-term best interests.

Sustainability

The capacity to maintain, support, or endure.

Renewable Resource

Any natural resource that can be replenished naturally with the passage of time.

Non-renewable Resource

A resource that is being used faster than it can be replaced.

By-catch

Unwanted marine creatures that are caught in nets while fishing for other species.

Aquaculture

The farming of aquatic organisms such as fish and mollusks.

Trawling

To fish with a trawl net.

Long-line

A fishing technique that involves hooking bait throughout a long line in intervals.

Drift-nets

Plastic nets up to 40 miles long that entangle thousands of fish and marine organisms.

Purse-seining

A large net shaped like a purse that encloses and catches fish.

Ecology

The study of organisms and their interactions with one another and their physical surroundings.

Abiotic

Non-living parts of the environment.

Biotic

Living things.

Natural Selection

The process whereby organisms better adapted to their environment tend to survive and produce offspring.

Species

A group of organisms that reproduce and produce fertile offspring.

Population

A group of the same species living in a particular area.

Community

Different species living together in a defined habitat with some degree of interdependence.

Ecosystem

A biological community of interacting organisms and their physical environment.

Biodiversity

The variety of life in the world or in a particular habitat or ecosystem.

Succession

Change in the species structure of an ecological community over time.

Zonation

Categorization of biomes into zones based on distribution and arrangement determined by environmental factors.

Primary Succession

Succession that begins with bare rock.

Secondary Succession

An ecological succession that occurs after a disturbance destroys existing vegetation.

Symbiosis

An intimate relationship between two or more organisms of different species.

Mutualism

A relationship between two species where both benefit from the association.

Parasitism

A symbiotic relationship where one organism benefits and the host is adversely affected.

Commensalism

A relationship beneficial for one organism while neutral for the other.

Interspecific Competition

Competition for resources between different species.

Intraspecific Competition

Competition for resources between members of the same species.

Niche

The role or function of an organism or species in an ecosystem.

Habitat

The natural environment or home of an animal, plant, or other organism.

Limiting Resource

A factor that controls the growth, abundance, or distribution of a population in an ecosystem.

Range of Tolerance

The range of conditions within which an organism can survive.

Keystone Species

A species that has a large effect on its environment relative to its abundance.

Species Richness

Biological diversity that encompasses the number of species in an area or community.

Edge Effect

The phenomenon in which ecotones between adjacent communities have more species or greater population densities.

Emigration

When individual organisms leave an area, decreasing the size of the population.

Immigration

When individual organisms enter a population, increasing its size.

Competitive Exclusion Principle

Two species that compete for the exact same resources cannot stably coexist.

Resource Partitioning

Where species share resources in an environment to minimize competition.

Indicator Species

An organism that provides an early warning of environmental damage.

Native (Indigenous) Species

A naturally occurring species within a particular environment.

Photosynthesis (equation)

6CO₂ + 6H₂O + Energy --> C₆H₁₂O₆ + 6O₂.

Respiration (equation)

C₆H₁₂O₆ + 6O₂ -----> 6CO₂ + 6H₂O + energy.

First Law of Thermodynamics

Energy can change forms but cannot be created or destroyed.

Second Law of Thermodynamics

In a closed system, usable energy is lost to heat over time.

Entropy

The measure of disorder in a system.

Open Systems

Systems that continuously interact with their environment.

Closed Systems

Systems where energy can be exchanged but not matter.

Isolated Systems

Systems where neither energy nor matter can flow in or out.

Autotrophs

Organisms capable of creating their own energy via photosynthesis.

Heterotrophs

Organisms that depend on complex organic material for nutrition.

Detrivores

Organisms that consume dead organisms.

Saprotrophs

Decomposers that break down dead organic material for energy.

Trophic Levels

Each level in a food chain, e.g., producers on the first level.

Food Web

A system of interlocking and interdependent food chains.

Food Chain

A series of organisms each dependent on the next for food.

Pyramid of Energy

An ecological pyramid representing relative energy value at each trophic level.

Pyramid of Numbers

An ecological pyramid showing relative numbers of organisms at each trophic level.

Pyramid of Biomass

An ecological pyramid that shows the amount of organic material at each trophic level.

Assimilation

Processes of photosynthesis and the absorption of raw materials by plants.

Ammonification

The conversion of organic nitrogen to ammonium by decomposers.

Nitrification

The oxidation of ammonium compounds into nitrites and nitrates.

Denitrification

The removal of nitrogen from soil or living organisms.

Nitrogen Fixation

Conversion of atmospheric nitrogen into a usable form.

Polar Molecule

A molecule with uneven charge distribution, such as water.

Non-polar Molecule

A molecule with no positive or negative poles.

Drainage Basin/Watershed

An area drained by a river or river system.

Surface Water

Fresh water found on Earth's surface.

Water Table

The upper surface saturated with groundwater.

Flood Plain

The area around a body of water that may be flooded at times.

Subsidence

The gradual caving in or sinking of an area of land.

Saltwater Intrusion

Contamination of freshwater sources with saltwater.

Potable Water

Water that is safe to drink.

Endocrine Disruptors

Substances that alter hormonal systems causing widespread effects.

Point Source Pollution

A single identifiable source of pollution.

Non-Point Source Pollution

Pollution from sources hard to identify, like agricultural runoff.

Eutrophic

Rich in organic and mineral nutrients, supporting abundant plant life.

Oligiotrophic

A lake lacking in plant nutrients, with a large amount of dissolved oxygen.

Contour Line

Lines joining points of equal elevation on a surface.

Confined Aquifer

An aquifer covered by an impermeable layer.

Unconfined Aquifer

Aquifers in which groundwater seeps directly into the aquifer.

Permeable

Having pores or openings that allow liquids or gases to pass through.

Zone of Aeration

Ground area containing both water and air, not completely saturated.

Zone of Saturation

Area below the water table, completely saturated in water.

Cone of Depression

Occurs in an aquifer when groundwater is pumped from a well.

Dead Zone

Low oxygen areas in bodies of water caused by human pollution.

Biological Oxygen Demand (BOD)

The amount of oxygen required by microorganisms to decompose organic matter.

Marsh

A wet, low-lying area characterized by grassy vegetation.

Swamp

A forested wetland partially covered with water.

Estuary

A coastal body of water where fresh and saltwater mix.

Delta

A landform formed at the mouth of a river.

Headwaters

The furthest point in a river from its mouth.

Nekton

Organisms that can swim freely, independent of currents.

Benthos

Aquatic organisms living on the bottom of the ocean floor or lake.

Pelagic

Organisms inhabiting the upper layers of the open sea.

Phytoplankton

Single-celled plant organisms drifting in the ocean.

Zooplankton

Plankton consisting of small animals.