I. Levels of Organization
Ecology = the study of the interactive relationships of living things with their environment.
    A. Organism: Any living thing.
    B. Population: group of individuals of the same species that live in same area at same time.
    C. Community:  all of the populations of different species living in the same area;  includes organisms of different species.
            1. Ex: all of the organisms in a forest
            2. Some communities have hundreds of populations (coral reef,rainforest). Others have only a few populations(desert)
    D. Ecosystem: all communities that live in an area, PLUS nonliving (abiotic) parts of environment (temp, rain, soil, etc)
            1.  Two types of environmental factors:
                    a. biotic factors - living
                    b. abiotic factors - nonliving
            2. Biome = Group of ecosystems with the same type of climate.
    E. Biosphere: Ttl. part of planet where organisms found, incl. all ecosystems on Earth. (from deepest ocean to highest atmosphere)
    F.    Habitat = Surroundings; Where an organism lives, its address
    G.   Niche =   The role; way of life a species pursues within its habitat.
           How much and what it eats,  moisture  requirements, required temperature, etc...its total way of life--Ex:  The red-tailed hawk and the great horned owl live in the same area and both prey on mice and other rodents.  So they occupy the same habitat. However, the hawks are active in the daytime and the owl is active at night - so they occupy different niches.

                   Organism ----->Population----->Community ----->Ecosystem -----> Biosphere

II. Flow Of Materials Within The Environment

• Major elements needed for life are C, H, O, N; also S, P, and other "trace" elements. When death occurs, these chemicals are returned to the earth and atmosphere. (RECYCLING-the "Circle of life")

                1.  The first half of the cycle is photosynthesis -  make food from light (plants, algae,etc = autotrophs)

• Plants, algae are main producers. Convert solar energy into chemical energy in the form of food (glucose).  This energy passes from one organism to another.

• Organisms that are able to convert solar energy or inorganic compounds into chemical energy that can be used by the organism are called autotrophs.  Organisms that cannot do this and rely on those autotrophs for food are called heterotrophs.

            3. Food Web - Network of interacting food chains (Ecosystems have more than one food chain--chains overlap cause organisms eat more than one type of food.
            4. Ecological Pyramids
                A. 90% energy LOST at each trophic level (10% KEPT)
Ex: Plant gets energy from the sun (uses some of the energy for food making and metabolism - about 90%.)
Rabbit eats the plant (gets only about 10% of what the plant did.)
Bobcat eats the rabbit (gets only about 10% of what the rabbit gets.)
5. BIOTIC RELATIONSHIPS
  A.  Competition and Predation
   1.   Competition = struggle for limited natural resources
       a.   Intraspecific competition = competition between members of the same species
       b.   Interspecific competition = competition between e different species
 
   2.   Predation = One organism preying upon or eating another organism.
       a. Prey  = the eaten
       b.  Predator = the eater
  B. Symbiosis
   1. Symbiosis = "Living Together"; a close relationship between 2 organisms of diff species
       a. Mutualism =  +/+  both organism benefit (ex:  lichen [algae and fungi])
       b. Commensalism = +/0 one benefits, the other is unaffected  (ex:  Spanish moss on trees)
       c. Parasiticism = +/- one benefits at the expense of the other (ex:  tick on a dog)
IV.  BIOLOGICAL RHYTHMS
Length of day, seasonal temperature, phases of the moon – all occur at regular intervals.
1. Biological rhythm = When an organism responds to naturally recurring phenomena, such as length of day, seasonal temperature, or phases of the moon, in a recurring pattern.
2. Circadian =  a rhythmic pattern of change that occurs in an organism  every 24 hours.
     a. diurnal - active during the day
     b. nocturnal - active at night
     c. Sleep and waking hours in humans is a circadian rhythm
3. Biological clock = internal chemical mechanism that controls circadian rhythms.
4. Annual rhythm = pattern of change occurring once a year.
     a. hibernation - reduction of activity of warm blooded animals during the winter
     b. estivation -  reduction of activity of warm blooded animals in summer
 
 
 

____ The nonliving factors of the environments are called
   a) abiotic factors           b) biotic factors        c) fundamental niche                d) resources

____ The range of resources a species actually uses is called
   a) an abiotic factor          b) a realized niche         c) resource tolerance                     d) a regulator

____ A symbiotic relationship in which one species benefits and the other is not effected is called
    a) commensalism          b) mutualism             c) parasitism                d) competition

____ All the organisms and the nonliving environment found in a particular place is called a(n)
     a) community             b) population        c) habitat               d) ecosystem

____ What is the study of organisms and their interactions with the environment?
    a) biology             b) environmentalism               c) ecology                   d) taxonomy

____ The living components of the environments are called
   a) abiotic factors          b) biotic factors        c) fundamental niche                d) resources

____ Organisms that break down and feed on organic mater are
    a) decomposers                   b) omnivores               c) synthesizers                  d) producers

____ Carnivores are animals that eat only
    a) plants            b) inorganic materials              c) other consumers                d) decomposers

____ All interacting organisms living in an area are called
     a) community             b) population        c) habitat               d) ecosystem

____ An example of an abiotic factor is
    a) tree               b) sunlight                   c) bird                  d) grass

____ Succession that occurs in an area where existing community has been partially destroyed is called
   a) primary succession         b) climax succession         c) secondary succession              d) pioneer succession

____ What is the source of almost all energy in most ecosystems?
    a) rock                   b) water                   c) radiation from sun                  d) carbon

____ All organisms of the same species that live in a locations are called a
   a) community             b) population        c) habitat               d) ecosystem

____ All the interconnected food chains in an ecosystem make up a
   a) biomass              b) biosphere              c) food pyramid                    d) food web

____ Photosynthesis and cellular respiration are part of which cycle?
    a) water            b) carbon                   c) nitrogen                 d) food

____ The nitrogen cycle is carried out primarily by
   a) humans           b) heterotrophs         c) bacteria                  d) fungi

____ The region of the earth that supports all living things is the
   a) life zone          b) biotic factor              c) biozone                   d) biosphere

____ The role an organism plays in its ecosystem is its
    a) niche                  b) biotic factor           c) abiotic factor                   d) ethology

____ The physical location of an ecosystem in which a given species lives is called a
    a) habitat               b) tropical level           c) community                 d) food zone

____ Ecology is the study of the interaction of living organisms
    a) with each other and their habitat                                     c) and their community
    b) with each other and their physical environment              d) and the food they eat

____ When an organism dies, the nitrogen in its body
    a) can never be reused by other living things                     c) is immediately released into the atmosphere
    b) is released by the action of decomposers                      d) None of the above

____ The bracket fungus is an example of
    a) a decomposer             b) a scavenger           c) an omnivore                d) an autotroph

____ An ecosystem consists of
    a) a community of organisms                     c) the soil, water, and weather
    b) energy                                                   d) All of the above

____ A group of organisms of different species living together in a particular place is called
    a) a community             b) a population           c) a biome               d) a habitat

____ The primary producers of a grassland ecosystem would most likely be
    a) insects             b) bacteria           c) grasses                d) algae

____ Organisms that manafacture organic nutrients for an ecosystem are called
    a) primary consumers         b) predators        c) primary producers              d) scavengers

____ The relationship between a producer and comsumer is best illustrated by
    a) a snake eating a bird                             c) a lion eating a zebra
    b) a fox eating a mouse                             d) a zebra eating grass

____ The diagram, which shows hoe energy moves through an ecosystem, is known as a
    a) habitat         b) food chain          c) food net              d) foood web

____ In a food web, which type of organism receives energy from every other type?
    a) producer         b) carnivore        c) decomposer              d) herbivore

____ Animals that feed on plants are at least in the
    a) first trophic level                                 c) third trophic level
    b) second trophic level                             d) fourth trophic level

____ The total dry weight of the organisms in an ecosystem  is called
    a) trophic level         b) biomass        c) energy level             d) ecomass

____ Becuase energy diminishes at each successive trophic level, few ecosystmes can contain more than
    a) two trophic levels                             c) five trophic levels
    b) four trophic levels                             d) eight trophic levels

Nitrogen gas in the atmosphere is converted to nitrogen compounds (ammonium and nitrates) during:
A) denitrification           B) nitrification   C) respiration               D) nitrogen fixation

Evaporation, condensation, and precipitation are processes that are involved in the:
A) carbon cycle            B) water cycle            C) nitrogen cycle          D) oxygen cycle

 The type of bacteria found in root nodules of legumes:
A) symbiotic nitrogen-fixing      B) free-living nitrogen-fixing  C) nitrifying       D) denitrifying

The source of carbon for higher-level consumers is:
A) CO2                B) plants, algae, and cyanobacteria                   C) primary consumers

 The main way that life contributes to the water cycle?
A) evaporation B) precipitation C) condensation           D) transpiration
 

TRUE or FALSE:

____ When an organism dies, the nitrogen in its body is released by decomposers.

____ The lowest trophic level of any ecosystem is occupied by the consumers.

____ Omnivores feed only on primary producers.

____ The greenhouse effect is a phenomenon caused by excess fossil fuels being burned.

____ Regulators change their internal conditions as their environment changes.

____ The realized niche of a species is the range or resources it actually uses,

____ If a prey species were removed from an environment, its predator species could dominate the environment,

____ Grasses are common pioneer species because they secret acids that dissolve rock, releasing minerals for plant growth.

____ Carbon moves from the biotic portion of its cycle into the abiotic portion during photosynthesis.

____ Deserts differ from other biomes in that they have high temperatures all year.

____ Producers in an ecosystem transfer all of their energy to primary-level consumers

____ A food chain is made up of interrelated food webs.

____ All organisms in an ecosystem are part of the food web of that ecosystem.

____ A change in the number of predators in a food web can effect an entire ecosystem.

____ Organisms at higher levels tend to be higher in number than those at lower trophic levels.

____ Ecologist call the physical location of a community its habitat.

____ Food chains usually begin with primary producers.

____ Ecosystems include only the biotic factors in an area.

____ A community includes all the species within an area.

____ Estuaries are areas of shallow water where fresh water flows into the sea.

____ Decomposers break down living organisms and thus help prevent population explosions of species.
 

MATCHING:

____ 1. community                      A. area rich in wildlife having two seasons-wet and dry

____ 2. generalist                        B. number of species and abundance of each

____ 3. ecology                           C. killing and consuming another organism

____ 4. resources                        D. where an organism lives

____ 5. habitat                             E. phenomenon that insulates Earth from the freezing temperature of space

____ 6. population                       F. interaction in which both species benefit

____ 7. greenhouse effect             G. nitrates converted into nitrogen gas

____ 8. global warming               H. deep water in the open ocean

____ 9. mutualism                         I.  eat other consumers

____ 10. species richness             J. members of a single species living in one place at one time

____ 11. parasitism                      K. organisms interacting in a specific area

____ 12. secondary succession     L. ammonia converted into nitrates and nitrites

____ 13. commensalisms              M. area with low rainfall, rich soil, and grasses

____ 14. primary succession         N. increases in global temperature due to trapped excess greenhouse gases

____ 15. predation                        O. sequence of species in a disturbed area

____ 16. species diversity              P. interaction in which one species benefits and the other is harmed

____ 17. nitrification                      Q. obtain nutrients from dead organisms

____ 18. decomposers                     R. ocean over continental shelf

____19. neritic zone                        S. number of species

____ 20. denitrification                   T. interaction in which one species benefits

____ 21. temperate grasslands        U. plants growing where bare rock was

____ 22. carnivores                        V. a species with a broad niche

____ 23. oceanic zone                   W. study of the interactions between organisms and their environment

____ 24. savannas                          X. energy and materials needed by a species
 
 

Answer the following questions

1. List the Five Levels of Organization in the environment.
 
 

2. What is a trophic level, and what determines an organism’s trophic level?
 
 

3. Why is so little of the energy from one trophic level transferred up to the next trophic level?
 
 

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