chapter 3.1-3.3 test Flashcards
why do ecologist ask questions about events and organisms that range in complexity from an individual to the biosphere
understand relationships with the biosphere
species
group of organism so similar to one another that the can breed and produce fertile offspring
populations
a group of individuals that belong to the same species adn live in the same area
community
assemblages or different populations that live together in adefined area
ecosystem
collection of all the organisms that live in a particular place, together with their nonliving, or physical enviroment
biome
a group of ecosystems that have the same climate and dominate communities
what is the highest level of organization that ecologist study
entire bisphere
3 basic approaches scientist us to conduct modern ecological research
observing, experiment, modeling
why might ecologist set up an artificial environment in a laboratory
intimate and manipulate conditions that organisms would encounter in the natural world
why are many ecological phenomena difficult to study
occur over a long period of time or on such large spatial scales
why do ecologist make models
gain insight into complex phenomena such as the effects of global warming on the ecosystem
what is the core of every organism’s inter reaction with the environment
need for energy to power life’s processess
what source of energy do organisms use that dont use the suns energy
inorganic chemical compounds
autotrophs
only plants, some algae, and certain bacteria can capture energy from the sunlight or chemicals and use that energy to produce food
why are autotrophs also called producers
they make their own food
what do autotrophs do during photosynthesis
use light energy to power chemical reactions that convert carbon-dioxide and water into oxygen and energy rich carbhydrates such as sugars and starches
what kind of autotroph is the main on land
plants
what is the main kind of autotroph in upper layers of ocean
algae
what is the main autotroph in tidal flats and salt marshes
photosynthetic
what are chemosynthesis
organisms use chemical energy to produce carbohydrates
heterotrophs are also called what
consumers
detretress
plant and animal remains and other dead matter
herbivore
animal that only eats plants ( cows, rabbits)
carnivore
organism that only eats meat (snakes, dogs, owls)
omnivore
organism that eats plants and animals (humans, bears, and crow)
detritivore
heterotroph that feeds on dead matter (mites, earthworms, crabs, and snails)
decomposers
breaks down organic matter (bacteria, fungi)
how does energy flow through an ecosystem
it flows through an ecosystem in one direction from the sun and inorganic systems to autotrophs and then to varies heterotrophs
food chain
a series of steps in which organisms transfer energy by eating and being eaten
food web
networks of complex interactions formed by the feeding relationships among various organisms in any ecosystem
what does a food web link together
all the food chains in the ecosystem
what is a trophic level
one of the levels in a food chain or a food web
in a food web, what organisms make up the first trophic level
producers
what does a consumer in a food chain depend on for energy
producers that would be on a lower level
what is an ecological pyramid
diagram that shows the relative amount of energy, contained with trophic level
only what level is producers
1st
what is a biomass
it is the total amount of living tissue within a trophic level
what does a biomass pyramid represents
represents the amount of potential food in that level
what does a pyramid of numbers show
number of organisms in each trophic level
why can each trophic level support only about one tenth the amount of living tissue as the level below it
each trophic level harvest only .1% of energy from the level below it
what is ecology
scientific stufy of interactions among and between organisms and their surroundings/ environment
