Biology Chapter 3
the scientific study of interactions among organsims and between organisms and their environment.
what does the biosphere contain?
Parts of the planet in which all life exists
How are human economics and ecology linked?
humans live within the biosphere and depend on ecological processes to provide such essentials as food and drinkable water that can be bought, sold, or traded.
Explain the relationship between ecosystems and biomes.
Examples of Biotic Factors,
animals, bacteria, mushrooms, and plants
Examples of Abiotic Factors.
sunlight, heat, precipitation, soil, and air.
both abiotic and biotic factors
air, and soil.
why might an ecologist set up and artificial environment in a laboratory?
see how growing plants react to different conditions of light, temperature, or carbon dioxide concentration.
why are many ecologists phenomena difficult to study?
they occur over such long periods of time or over such long distances.
why do ecologists make models?
to help them understand phenomenas.
what do autotrophs do during photsynthesis?
they capture light energy and use it to convert carbon dioxide and water into oxygen and sugars.
can some organisms survive without energy from the sun. Explain.
yes, chemosythesis which is the process in which autotrophs use chemical energy to produce carbohydrates
can organisms create their own energy? Explain
no, they can only use it from other sources, which mostly come from the sun.
heterotroph that eats plants, ex: cows, and rabbits
heterotroph that eats animals, ex: snakes, dogs, eats, and river otters
heterotroph that eats both plants and animals.ex: humans, bears, and pigs
heterotroph that eats the remains of plants and animals
heterotroph that chemically break down organic matter to obtain energy
heterotroph that consumes the carcasses of dead animals but does not typically kill them itself.
what is a consumer
organism that relys on other organisms for energy and nutrients
how would you categorize a consumer that eats prey and dead animal carcasses
what role o producers play in establishing earth as a living planet?
producers are at the bottom of the food chain and if they are not there many species would die.
a chemical substance that an organism needs to survive
a process in which producers use chemical energy to make carbohydrates
an organism that feeds on other organisms
all the organisms in one area and their physical environment
a process in which producers use light energy to make carbohydrates
the study of the biosphere
an organism that uses chemical or light energy to produce its own food supply
the portion of the earth and its atmosphere that contains organisms
ecologist measure what in grams of organic matter per unit area
why do we study ecology?
we live in a natural world and use its resources, natural effects our lives, and protect biodiversity
non-living, physical componets, necessary for biotic to survive, ex: heat, weather, temp, current, and soil
living, biological influences, compete for food and space
how do we study ecology
observe, experimenting, modeling
all life on earth exists in....
which term describes a group of different species that live togethere in a defined area?
name the different levels of organization within the biosphere from smallest to largest
individual organsism, population, community, ecosystem, biome, biosphere
how do ecologists use modeling?
understand phenomenas which are events that are difficult to study.
give an example of how a biotic factor might influence the organisms in an ecosytem.
one organsims can consume another and if one organism is killed off it affects the rest.
primary producers are organisms that..
use energy they take in from the environment to convert inorganic molecules into complex organic molecules
how do all consumers get their energy?
from eating organisms that are living or were once living
the series of steps in which a large fish eats a small fish that has eaten algea
the total amount of living tissue at each trophic level in an ecosystem can be shown in...
whic group of organisms is always found at the base of the food web or food chain?
why is the transfer of energy in a food chain usually only about 10 percent efficient?
organsims spend much of their energy they acquire on life process and some energy is given off as heat
nunutrients move through an ecosystem in
which biogeochemical cycle does not include a major path in which the substance cycles through the atmosphere?
list two ways in which water enters the atmosphere in the water cycle?
evoporation of water directly from a body of water or transpiration...
explain nitrogen fixation
is the process where bacteria convert nitrogen gas into ammonia...
what is meant by "nutrient limitation"?
a nutrient is in a short supply.
phyramids of energy
show relative amounts of energy available at different trophic levels
pyramids of biomass
ahow the total amount of living tissue at each trophic level
pyramid of numbers
shows the relative number of organisms at different trophic levels
what are the four elements that make up 95% of the body?
oxygen, carbon, nitrogen, and hydrogen
chemical and physical process include what?
clouds and precipitation, action of lightning, and flow of running water
why is the earth considered a closed system
all matter is recycled in our biosphere
how do humans add nitrogen to the biosphere?
the use and manufacturing of fertilizers
compare abd contrast the flow of energy and the flow of matter through the same environment?
flow of energy flows one way, and the flow of matter can be recycled. they both flow through an organsim
cycle which involves photosynthesis and human activities such as burning
is the key ingredient to all organic matter
cycle which nitrogen fixation and denitrification
is needed by all organisms to build proteins
cycle which phosphorus is stored in rocks and ocean sediments and later is gradually released into water and soil.
needed for molecules such as DNA, and RNA.