Regents Review 4

Ecology: The Biosphere

Ecology Basic Terms

• Define the term biotic• Biotic – living part of the ecosystem

• Plants• animals

• Define the term abiotic• Abiotic – the non-living portion of the ecosystem

• Light• Water• Gases• Mineral• Rocks

Basic Terms continued

• Define Autotroph/Producer.

• Organism that can produce its own food source. Example: Plants and some bacteria

• Define the term Heterotroph/Consumer

• Organisms that must feed on other biotic factors to acquire energy. Example: humans

Organization

• Define biosphere

• Area where life is contained including all land, water and air

• State the order organization of the biosphere from most specific to most broad

• Species, Population, Community, Ecosystem, Biome, Biosphere

Organization continued

• Define species. Give an example• Species: a group of organisms so similar to one

another that they can breed and produce fertile offspring. Example: humans, great danes, moose, etc.

• Define Population. Give an example• Population: groups of individuals that belong to

the same species and live in a given area. Example: All great danes, all moose

Organization continued

• Define Community. Give an example• Community: assemblage of different populations

that live in a defined area. Example: All humans and moose and dogs in a given area

• Define Ecosystem• Ecosystem: collection of all populations and the

abiotic factors living in a given area• Define Biome. Give an example• Biome: group of ecosystems that have the same

climate and similar dominant communities. Example: desert, rainforest, deciduous forest

Energy Flow

• State the original source of all energy on the planet

• The Sun

• How does the energy get into the ecosystem?

• Plants

• By which process?

• Photosynthesis

Energy Flow continued

• How can energy flow be visually expressed?

• Energy Pyramid

• Which organisms would we find at the base of the pyramid?

• Producers

• At the next few consecutive levels?

• Consumers

Types of Consumers

• Define the term Herbivore. Give an example• Herbivore – organisms that consume plant

matter. Cows, sheep• Why are they considered primary consumers?• First to acquire energy from the plant• Define the term Carnivore. Give an example• Carnivore – organisms that that eat plant eating

and meat eating organisms. Snakes, lions, tigers, bears …oh my!!

Consumers continued

• Why can carnivores be considered secondary, tertiary, etc. consumers?

• Depending if they eat primary consumers, secondary consumers, etc.

• Define the term Omnivore. Give an example• Omnivore – an organism that consumes both

plant and animal matter. Humans• Define the term decomposer. Give an example• Decomposer – organism that consumes dead or

decaying matter. Examples: Bacteria, fungi

Energy Pyramid

• What is the name given to each energy level?

• Trophic levels• Why do the trophic levels

get smaller with each successive level?

• Energy is lost to life functions and only a small percentage is passed on

• How much energy is available or transfer at each level?

• 10%

Energy Pyramid

• How would the energy flow be affected if the producers were lost or reduced in numbers?

• The pyramid would collapse or sustain less organisms

Food Web vs. Food Chain

• Define food chain. Give an example• Series of steps in a single direction from

producer to last consumer• Example: Seed – mouse – snake – owl• Define food web. • Number of intertwining/connected food chains• Why is the food web more stable than a food

chain?• More energy pathways so energy flow will not be

completely stopped if one organism is lost

Food Web vs. Food Chain

Biomass Pyramid

• Define the term biomass

• Biomass – is the total dry weight of an organism

• Why must biomass decrease as you move up the energy pyramid on land?

• Each level must have enough mass to sustain the next level above it

Cycling of Materials

• Identify materials that are recycled through the environment

• Water, carbon, oxygen, etc.• Is energy recycled?• NO!!!!• Why must some materials be recycled

while others do not?• Limited resource on the planet. Energy

comes from the Sun

Carbon Cycle

• Briefly describe the cycling of carbon in the ecosystem

• Enters through photosynthesis – converted to glucose – passes to consumer when eaten – released by cell respiration as carbon dioxide into the environment

• Briefly describe the nitrogen cycle

Organismal Interactions• Define the term predation. Give an example• One organism feeds another. Wolf and moose, tiger and gazelle• Define the term Mutualism. Give an example• When both organisms benefit from the interaction. Example:

Humans and intestinal bacteria• Define Commensalism. Give an example• Commensalism – when one organism benefits from the interaction

and the other does not gain or lose anything. Example: Whales and barnacles

• Define the term Parasitism. Give an example.• Parasitism – one organism lives on or in another and benefits with

the host is harmed. Example: tapeworm and human

Succession

• Define primary succession. Give an example• Primary succession – development of an

ecosystem from no life• Explain the importance of a pioneer organism.

Give an example• Lichen is an example• Define secondary succession. Give an example• Secondary succession – recovery of an

ecosystem after a natural disaster or human influence. The resulting ecosystem can be the same or different from the original ecosystem