Adaptations and Environmental Factors

Where organisms live is dependent upon the environmental factors present. Organisms require particular physical conditions as well as nutrients, water, oxygen and carbon dioxide so that they can survive and reproduce. Organisms have structural, physiological and behavioural features that are adaptations which enable them to live in the environments in which they do.

VCE YEAR 11

UNIT 2: ORGANISMS AND THEIR ENVIRONMENT

AREA OF STUDY 1: ADAPTATIONS OF ORGANISMS
 VCAA 2006 VCE STUDY DESIGN

BIG IDEA: ADAPTATIONS ARE THE RESULT OF ENVIRONMENTAL PRESSURES


newdevil_arid.jpg
Thorny Devil (Moloch horridus) has adaptations to suit arid environments

What you intend the students to learn about this idea.

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Wedell Seal Pup
Weddell Seals live in the cold waters around Antarctica. They are well suited to this environment which can be seen by the features they have.
Abiotic Factors - cold water, solid ice, oxygen
Biotic Factors - availability of food source (fish, crabs), predators (orcas, leopard seals), mate for reproduction, disease causing organisms
Structural features that Weddell Seals have to live in their environment - High level of underwater vision, modified teeth to maintain holes in ice to breathe, stealth hunters
Evans, Ladiges, McKenzie, Sanders, 2005. Biology 1. Port Melbourne:Heinemann

  • Adaptations are inherited characteristics that increase the survival and reproductive likelihood of living organisms.

  • Organisms distribution is determined by the features they have which determine whether they are well suited to a particular environment.

  • Adaptations that evolve in species are the result of selection pressures on them throughout their evolution.

  • There are three types of adaptation in organisms which enable them to survive and reproduce in ever changing environments ie. physiological, anatomical and behavioural.

  • There is a relationship between the environment, adaptation and distribution.


  • An organisms environment consists of their abiotic(physical surroundings) and biotic(other organisms) environments.

  • Living organisms require adequate levels of nutrients, water, oxygen, carbon dioxide and suitable environmental conditions (eg. light, temperature, humidity) to survive, grow and reproduce.

  • Limiting factors are any environmental requirements that are in limited supply - this can affect distribution.

  • All organisms have tolerance limits for a range of factors, these are the limits between which they can survive.

Nelson Biology VCE 1 & 2, 2006. South Melbourne
Why it is important for students to know this.
  • So students can understand why particular organisms can only live in certain environments

  • It will help students to understand ecosystems, natural selection, evolution and genetics in future study areas

  • So students will understand that any change to the environment, natural or human induced, can have an effect on the distribution and survival of organisms

  • By understanding abiotic and biotic environments students should have a better understanding of particular adaptations
What else you know about this idea (that you do not
intend students to know yet).
  • Students need to be aware that there are three types of adaptation; anatomical, physiological and behavioural. However, the different types of adaptation will be covered in detail later in the unit.
Knowledge about students' thinking/difficulties connected
with teaching this idea.
  • Students may confuse the scientific term adaptation with the idea of adapting or getting used to.

  • Students should have already learnt the requirements of living organisms in Unit 1.

  • Students may have trouble grasping the time taken for changes to occur.
Teaching procedures (and particular reasons for using
these to engage with this idea).
anemone.jpg
sea anemone and anemone fish

  • Show the following video on shoreline habitats as a review on habitats. After the video, what adaptations does a ghost crab have so it can live in this particular environment? List abiotic and biotic factors for the ghost crab.

http://videos.howstuffworks.com/hsw/10216-beach-shorelines-animal-life-in-shoreline-habitats-video.htm

  • As a class make a list of abiotic and biotic factors. Divide the abiotic and biotic factors into regional and local factors. This activity will encourage all students' participation and by the end they should have a good understanding of abiotic and biotic factors. See Learning Activity 1 on page 0.1 for more detail.

Other learning activities for this topic:
  • Draw a concept map to show the relationship between the above highlighted words: adaptations, distribution, physiological, anatomical, behavioural, environment, abiotic, biotic, limiting factors, tolerance limits. This exercise will show how well the students have understood the topic and how deep their understanding is.
  • Go to the website below and design an animal that has structural, physiological and behavioural characterisitics that make the organism well suited to a chosen biome.
http://school.discoveryeducation.com/lessonplans/activities/makeitahabitat/adaptations.html
Specific ways of ascertaining students' understanding or
confusion around this idea (include likely range of
responses).
The above teaching procedures should ascertain students' understanding of the topic at this beginning stage. Its important that students' have a good understanding at this stage to avoid confusion later in the topic.