Chapter 4


Study of the interaction of living organisms with one another and with their nonliving environmrnt of matter and energy; study of the structure and functions of nature.

Any form of life
Eukaryotic Organism

a cell containing a nucleus, a region of genetic material surrounded by a membrane. Membranes also enclosed by saeveral internal parts.

Prokarytotic organism
Cell that does not have a nucleus and internal parts are not enclosed by a membrane.

Group of organusms that resemble one another in appearence, behavior, chemical makeup and proccesses, and genetic struce.

Asexual reproduction

common in species such as bacteria with only one cell which divides to produce 2 identical cells that are clones or replicas of the original cell

Sexual reproduction
occurs in organisms that produce offspring by combining sex cells or gametes from both parents.
consists of a group of interacting individuals of the same species that occupy a specific area at the same time.
Genetic diversity
Variability in the genetic makeup amoung individuals within a single species.
Place or type of place where an organism or population of organusms lives
populations of all specias living and interacting in an area at a particular time
Communityof different species interacting wiht one another and with the chemical and physical factors making upits nonliving environment
Whole mass of air surrounding the earth.
Innermost layer of the atmosphere. It contains about 75%  of the mass of earth’s air and extens about 11 miles above sea level.
Second layer of the atmosphere, extending 11-30 miles above the earths surface. It contains small amounts of gaseous ozone qhich filters about 95% of ultra violet radiation emitted by the sun.
The earth’s liquid , frozen water, and small amounts of water vapor in the atmosphere

Zone of the earth where life is found. It consits of parts of the atmosphere, hyrdosphere, and lithosphere where life is found.

Natural Greenhouse effect

Heat built up in the triosphere because of the pressure of certain gases called green house gases. WIthout this effect, the earth would be cold.
Terrestrial regions inhabited by certain types of life, especially vegetation.
Physical properties of the troposhere of an area based on analysis of its weather records over a long period
Aquatic life zones

Marine and freshwater portions of the biospher.

(ex. lakes, streams, estuares and coastlines)

Tranditional zone in which one type of ecosystem tends to merge with another ecosystem.
living organisms
Range of tolerance
Range of chemical and physical conditions that must be maintained for populations of a particular species to stay alive and grow, develop, and function normally.
Law of tolerance
Existence, abundance and distribution of a species in an ecosystem are determined by where the levels of one or more physical or chemical factors fall within the range tolerated by the species
Limiting Factor
Single factor that limits the growth, abundance, or distribution of the population of a species in an ecosystem.
Organism that uses solar energy or chemical energy to manufacture the organic compounds it needs as nutrients from simple inorganic compounds obtained from its environment.


see producers

Compex process that takes place in cells of green plants. Radiant energy from the sun is used to combine carbon dioxide  and water to produce oxygen  and carbohydrates and other nutrient molecules
Process in which certain organisms extract inorganic compounds from their environment and convert them into organic nutrient compounds without the presence of sunlight.

Organism that cannot synthesize the organic nutrients by feeding on the tissues of preoducers or of other consumers


see consumer


Plant eaters
Primary consumers

Organism that feeds on all or part of plants (herbiovore) or on other producers

Animal that feeds on other animals
Secondary consumers
Organism that feeds only on primary consumers
Tertiary consumers
Animals that feed on animal-eating animals.
Animal that can use both plants and other animals as food sources

Organism that feeds on dead organisms that were killed by other organisms or died naturally.


Consumer organism that feeds on detritus, parts of dead organisms and cast-off fragments and wastes of living organisms.
Detritus (feeder)
Parts of dead organisms and cast-off fragments and wastes of living organisms
Organisms that digests parts of dead organisms and cast off fragments and wastes of living organisms by breaking down the complex organic molecules in those materials into simpler inorganic compounds and then absorbing the soluble nutrients. Producers return most of these chemicals to the soil and water for reuse.
Aerobic respiration

Complex process that occurs in the cells of most living organisms

use oxygen to convert organic nutrients

Anaerobic respiration

 Breaking down glucose without useing oxygen


Genetic Diversity
Variability in the genetic makeup among individuals within a single species.
Species diversity
Number of different species and their relative abundances in a given area
Ecological diversity
Variety of forests, desrts, grasslands, oceans, streams, lakes and other biological communities interacting with one another and with their nonliving environment
Functional diversity
Biological and chemical process of functions such as energy flow and matter cycling needed for the survival of species and biological communities.

Organic matter produced by plants and other photosynthetic producers; total dry weight of all living organisms that can be supported at each trophic level in a food chain or web; dry weight of all organic matter in plants and animals in an exosystem; plant materials and anumal wastes used as fuels

(the dry weight of all organic matter contained in tits organism)

Food web
Complex network of many interconnected food chains and feeding relationships.
Ecological efficiency

% of energy transferred from one trophic level to another in a food chain or web

Pyramid of energy flow
Diagram representing the flow of energy through each trophic level in a food chain or food web. With each energy transfer only a small part of the usable energy entering one trophic level is transfered to the organisms at the next trophic level
Gross primary productivity (GPP)
Rate at which an ecosystem’s producers capture and store a given amount of chemical energy as biomass in a given lenght of time.
Net primary productivity (NPP)

Rate at which all the plants in an ecosystem produce net useful chemical energy; equal to the difference between the rate at which the plants in an ecosystem produce useful chemical energy;and the rate at which they use some of that energy through cellular repiration.