Biology 12

Chapter 13 Ecological Principles • MHR 461

CHAPTER 13 REVIEW

Summary of Expectations

Briefly explain each of the following points.

• An organism’s environment consists of both
  abiotic and biotic features. (13.1)


• Individuals are part of populations,
  communities, and ecosystems. (13.1)


• Ecosystems and communities change over
  time as a result of ecological succession. (13.1)


• Range, habitat, ecological niche, and biome are
  all terms describing different aspects of where
  a species lives or what role it plays in a
  community. (13.1)


• The movement of energy and nutrients in
  ecosystems is affected by the trophic structure
  of communities. (13.2)


• Autotrophs (primary producers) form the first
  trophic level, which sustains all of the higher
  levels. (13.2)


• The number of consumers and the biomass at
  each level is limited by the inefficiency of
  energy transfer between levels. (13.3)


• Primary productivity, biomass, and the
  abundance of organisms are usually highest at
  the first trophic level and decrease at each
  successive level. With respect to these three
  features, the trophic structure of an ecosystem
  can be represented by a pyramid. (13.3)


• Energy flows through, whereas nutrients cycle
  in, ecosystems. (13.4)


• The biogeochemical cycles of elements that
  exist in gaseous form differ from those
  elements that exist in another form. (13.4)
  
  
  • Nutrients held in some environmental
    reservoirs are unavailable to living things,
    whereas in other reservoirs they are easily
    accessed by organisms. (13.4)
  
  
  • Plants act to conserve nutrients within
    ecosystems. (13.4)
  
  
  
  

Language of Biology

State the biological significance of each of the

following terms. Use these terms in concept maps to

show your understanding of how they are related. Be

prepared to explain your rationale.

• ecology • generalist


• biotic • trophic structure


• abiotic • trophic level


• population • primary producer


• community • primary consumer


• ecological succession • secondary consumer


• colonizer • tertiary consumer


• climax community • decomposer


• secondary succession • food chain


• primary succession • food web


• pioneer species • primary productivity


• ecosystem • biomass


• biosphere • pyramid of productivity


• biome • biomass pyramid


• habitat • pyramid of numbers


• range • biogeochemical cycle


• ecological niche • fossil fuels


• specialist

1.If the habitat of a species can be compared to
an address, and its ecological niche can be
compared to a job or occupation, what
metaphor might you use to describe its range?

2.In your notebook, state whether each of the
following statements is true or false. Correct
each false statement and explain your
reasoning.
(a)All members of a particular population
belong to the same species.
(b)All members of a particular species belong
to the same community.
(c)A species with a diverse diet is probably a
habitat specialist.
(d)Species living in the same habitat can have
different ecological niches.

(e)Species with different ecological niches can

live in different habitats.

(f )All members of the same species live in the

same type of habitat.

(g)Cellular respiration does not occur in the

cells of autotrophs.

(h)Heterotrophs are not capable of

photosynthesis.

(i)There are generally more tertiary consumers

than secondary consumers in an ecosystem.

(j)There are generally more primary producers

than primary consumers in an ecosystem.

3.Why are there typically only three to five

trophic levels in an ecosystem?

UNDERSTANDING CONCEPTS