Ecology Unit Key Understanding(s)

  • The amount of life an environment can support is limited by the ability of the ecosystem to recycle materials.
  • There is a continuous exchange of materials/energy between the living organisms and the Earth, and the balance of nature is sustained when losses equal to replacements.

Generalizations contextualized in unit:

  • SYSTEMS: The ecosystem is a collection of living organisms that interact with each other, and with its environment, to combine and determine the nature and behavior of the ecosystem.
  • CHANGE: The ecosystem is a delicate balance that depends on the balance of relationships within the system.
  • CHANGE: Interactions and behaviors of organisms can be explained as organisms adapt and adopt new strategies in response to each other and the environment. E.g. ecological relationships such as predator prey relationships and symbiosis.

Learners’ Outcomes

Students should be:
o Able to appreciate the various levels of ecological organization, and how they interact with one another through
a continuous exchange of materials/energy in order to support life.
o Aware of the various biomes in the world, and explain the factors that influence the differences in diversity –
history, climate, physical features and interactions with other organisms. (Biozone pages 282 – 284).
o Explain how energy losses occur along food chains, and discuss the efficiency of energy transfer between trophic levels.
o Emphasis is on the flow of energy and how organisms have been adapted to survive - living examples are the result of natural selection. (Biozone pages 300 – 304, 307 – 311).
o Able to relate how autotrophs, heterotrophs, biotic factors and abiotic factors are inter-connected to one another through energy transference and material exchange in an ecosystem. (Biozone pages 285 – 288).
o Describe the basis of species interactions and symbiotic relationships, and their influences on population changes, (Biozone pages 294 – 295, 323 – 330) i.e.,
- predator-prey and producer-consumer relationships.
- symbiotic relationships: commensalism, mutualism and parasitism.
- Inter-species and intra-species competition.
o Explain the role of defense mechanisms in predation and competition, e.g., mimicry, protective coloration, toxins, behaviour.
o Identify the main driving force driving the vast array of adaptations and survival strategies found in Nature – predator prey relationships.
o Understand how sampling techniques can be used to determine population size, diversity of organisms found in an area, and their distribution. (Biozone pages 356 – 361, 363 – 364).