35 terms

Biology: 3.1, 3.2 and 3.3 Study Guide


Terms in this set (...)

• Ecology
is the study of how organisms interact with each other and their environment.
Levels by which an Ecologist would study living things: smallest to largest
• Individual Organism
• Species
• Population
• Community
• Ecosystem
• Biome
• Biosphere
• Species
- is a group of similar organisms that can breed and produce fertile offspring.
• Population
- is a group of individuals that belong to the same species and live in the same area.
• Community
- is an assemblage of different populations that live together in a defined area.
• Ecosystem
- All the organisms that live in a place, together with their physical environment is
• Biome
- is a group of ecosystems that share similar climates and typical organisms.
• Biosphere
- consists of all life on Earth and all the parts of the Earth in which life exists, including land, water and the atmosphere.
2 processes by which producers obtain energy
• Photosynthesis
• Chemosynthesis
• Photosynthesis
-captures light energy and uses it to power chemical reactions that convert carbon dioxide and water into oxygen and sugars.
• Chemosynthesis
- some organisms can convert chemical energy from the interior of the earth into usable energy.
Types of Consumers
• Carnivores
• Scavengers
• Decomposers
• Herbivore
• Omnivores
• Detritivores
• Carnivores
- kill and eat other animals (wolf)
• Scavengers
- consume the carcasses of dead animals (vulture)
• Decomposers
- organisms that feed by breaking down decaying matter (fungi)
- eat plant matter (deer)
- eats both plants and animal matter (humans)
- feed on detritus, and digest decomposers that live on, and in detritus particles (earth worms)
• Environment
- refers to all conditions, or factors that surround an organism.
• Biotic Factors
- any living part of the environment.....animals, plants, bacteria
• Abiotic Factors
- any non-living part of the environment.....wind, heat, precipitation, sunlight
• Autotrophs
- are organisms that use solar or chemical energy to produce food.
• Primary Producers
- are the first producers of energy-rich compounds that are later used by other organisms.
• Heterotrophs
- must acquire energy from other organisms.
• Consumers
- another word for heterotroph
a series of steps in which organisms transfer energy by eating and being eaten.
network of feeding interactions
much more complicated than a food chain.
Each step in a food web or food chain is called a
Primary producers always make up the
first trophic level.
Ecological pyramids show the
relative amount of energy or matter contained within each trophic level in a given food chain or food web.
Three types of ecological pyramids:
1. Pyramids of energy,
2. Pyramids of biomass
3. Pyramid of numbers
Pyramids of energy
show the relative amount of energy available at each trophic level of a food chain or food web.
is the total amount of living tissue within a given trophic level.
2. Pyramids of biomass
show the relative amount of living organic matter available at each trophic level in an ecosystem.
3. Pyramid of numbers
the relative number of individual organisms at each trophic level of an ecosystem.