SNC 1W1 - Ecology/Biology Unit Review

**Photosynthesis**

 plants convert solar energy (chlorophyll, the green pigment

plants) to chemical energy - carbon dioxide + water = glucose +oxygen

**Cellular Respiration**

all living things, process by which living, things get energy from glucose - glucose + oxygen = carbon dioxide + water

**Biomass**

the total mass of living organisms in a defined group/area

**Trophic-Efficiency**

a measure of how much of the energy in organisms at one trophic level is transferred to the next higher level - 10% (grass biomass: 1000 units of energy -> caterpillar biomass -> 100 units (10%)

**Fermentation**

 process that releases energy from glucose in the absence of oxygen (bacteria uses fermentation to release the energy in glucose)

**Biosphere**

all the water found on earth in which life exists

**Lithosphere**

the hard part of earth’s surface

**Hydrosphere**

all the water found on earth

**Atmosphere**

the layer of gasses above Earth’s surface

**Biome**

a large geographic area with a characteristic climate, made up of many communities

**Ecosystem**

 interactions between living and their non-living environment (oceans forests, meadows)

**Community**

all the organisms that inhabit a particular area; consists of many populations of different species

**Population**

group of individuals of the same species living together in the same area at the same time

**Individual**

each organism of a species in a population

**Species**

group of organisms that resemble one another in appearance, behavior, chemical processes and genetic makeup (able to reproduce and produce fertile offspring) 

**Biotic**

the living factors in an ecosystem

**Abiotic**

 the non-living factors in an ecosystem

**Ecology**

the study of the interactions of living things with each other and with the non-living environment

**Symbiosis**

interaction between members of two different species that live close together in close association

**Predation**

occurs when one organism (predator) consumes another organism (prey) for food

**Competition**

occurs when two or more organisms compete for the same resources in the same location and time

**Water**

to survive-regulating body temperature or get rid of waste

**Oxygen**

for their life processes

**Light**

photosynthesis is a life process to produce their own food

**Nutrients**

 to grow, all organisms need nutrients (nitrogen and phosphorus)

**Soil**

provides nutrients for plants and also a habitat for microorganisms

**Autotroph/Producer**

uses energy and raw materials to make its own food (e.g. food)

**Heterotroph/Consumer**

must eat producers or other consumers to survive (e.g. lions, fish, shark)

**Herbivore**

plant eating animals (e.g. rabbit, cow, grasshopper)

**Carnivore**

animal that feeds on other animals (tiger, weasels, owls)

**Omnivore**

animals that eat both plants and animals (frogs, deer)

**Decomposer**

**a**n organism that breaks down detritus to get nutrients for their own use (e.g. bacteria)

**Ecotone**

a transition area between ecosystems where organisms from both ecosystems can interact

**Food Web**

a pictorial representation of the feeding relationships among organisms in an ecosystem

**Food Chain**

step by step sequence linking organisms that feed on each other

**Biodiversity**

the number of species in an ecosystem and their connection to each other

**Detritus**

wastes from plants and animals including their dead remains

**Bioaccumulation**

toxic chemicals are transferred to organisms

**Greenhouse Gasses**

atmospheric gasses that prevent heat from leaving the

atmosphere-increasing the temperature of the atmosphere (e.g. methane, water vapor)

**Greenhouse Effect**

 the warming of earth from greenhouse gases - trap some of the energy that would leave earth

**Climate Change**

the increase in earth’s average surface temperature (factors - increased concentration of carbon dioxide & increase in other greenhouse gasses, such a methane

**Natality**

the number of off-spring of any species in one year (increasing)

**Mortality**

the number of individuals of a species that die in one year (decrease)

**Immigration**

number of individuals of a species moving into an existing population (increase)

**Emigration**

number of individuals of a species moving out a an existing population (decrease,)

**Open Population**

all 4 factors act on it's individuals (e.g. forest, lake)

**Closed Population**

only natality and mortality act on it's individuals (e.g. zoo, laboratory, animal reserve)

**Population Growth**

(births + immigration) - (deaths + emigration)

**Growth Rate**

population growth/initial population × 100%

**Ecological Footprint**

 a measure of the impact of an individual or population on the environment (e.g. energy consumption, land use, waste production)

**Sustainability**

using earth’s resources at levels that can continue forever

**Stewardship**

 the active assumption of responsibility by humans for the welfare of the environment

**Restoration Ecology**

the renewal of degraded or destroyed ecosystems through active human intervention (to stimulate natural processes of regeneration to produce a sustainable ecosystem

**Reforestation**

the regrowth of a forest either through natural processes of planting seeds or trees in an area

**Wetlands Restoration**

 a process in which a wetland is returned to its natural state in terms of soil quality/composition, water coverage, types of plants that grow there and habitat

**Biocontrol**

the use of a species to control the population growth or spread of undesired species

**Bioremediation**

the use of living organisms to clean up contaminated areas naturally (e.g. bacteria has been used to break down oil spills

**Bioaugmentation**

the use of organisms to add essential nutrients to depleted soils (e.g. clover is often planted to replenish nitrogen levels in soil)

**Alien Species**

 species that are not native to an ecosystem - are invasive, that they take over the niche of existing species in an ecosystem due to lack of predators

**Overexploitation**

 the use or extraction or of a resource until it is depleted which can pose a threat to biodiversity - great reduction in population numbers and to species extinction

**Ecological Niche**

the way an organism occupies a position in an ecosystem including the necessary biotic and abiotic factors (e.g. food, habitat use, time)

**Mutualism**

 a symbiotic relationship between two species which both benefit from the relationship (e.g. coral provides algae, a protected environment and compounds they need for photosynthesis)

**Parasitism**

an organism whose niche is dependent on a close association with a larger host organism 

**Bioaccumulation**

a process in which materials, especially toxins, are ingested by an organism at a rate greater than they are eliminated

**Biomagnification**

the increase in the concentration of a toxin as it moves from one trophic level to the next

**DDT/PCBs**

 an agricultural insecticide that affected reproduction in fish-eating birds

**Pesticides**

chemicals that repel, kill, prevent or regulate the growth of unwanted biological organisms (e.g. can control fungi, weeds, insects plant diseases and small

animals) - which act by preventing electrical messages from traveling to the brain to the muscles that control breathings/movement thus killing the target/vulnerability

**Human Made Eutrophication**

the natural process of eutrophication ordinarily takes hundreds or thousands of years, which is artificially sped up by adding biodegradable wastes to the water

**Natural Eutrophication**

a process in which nutrient levels in aquatic ecosystems increase, leading to an increase in the population of primary producers

**Nutrient Cycles**

are needed by living things and are continually cycled through ecosystems 

**Water Cycle - Hydrosphere**

enters from precipitation of clouds, exits from evaporation caused by heating, absorbed by plants (impacted by pollution, climate change)

**Carbon Cycle - Atmosphere**

enters when organisms die and their bodies decompose, exits by photosynthesis (impacted by burning fossil fuels, changing land use)

**Nitrogen Cycle - Hydrosphere**

enters through rivers from continents and wet/dry deposition from the atmosphere, exits through deposition to sediments in the bottom of oceans and through release to the atmosphere in areas of biological activity (impacted by ocean dead zones and air pollution)

**Phosphorus Cycle - Hydrosphere**

enters between the surface and depths of the ocean, exits by cycling back to the ocean bottom as individuals due and fall to the ocean floor releasing assimilated phosphorus (impacted by detergents, sewage waste)