1. Biology:
Adaptation

2. Different types of environment
Biology:
Adaptation
There are three major types of environment. What are they?
land
freshwater
marine
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How do organisms survive in such different environments?

3. What is adaptation?
Biology:
Adaptation
All organisms are adapted to life in general, such as having legs for walking, wings for flying or leaves for photosynthesizing. These are general adaptations.
Teacher notes
See the ‘Competition’ presentation for more information on niches and other ecological terms.
Organisms also have specific adaptations. These are special features or behaviours that have evolved to make an organism particularly suited to its environmental niche.

4. A shark’s general adaptations
Biology:
Adaptation
What are a shark’s general adaptations to life in an aquatic environment?
streamlined shape to reduce friction when moving through water
gills have a large surface area so that oxygen can be
extracted from the surrounding water
Photo credit: © 2006 Jupiterimages Corporation
fins provide stability, power and control

5. A shark’s specific adaptations
Biology:
Adaptation
What are a shark’s specific adaptations to life as an aquatic predator?
specialized sense organs can detect the sound, movement and electrical fields of other organisms
highly sensitive sense of smell that can detect drops of blood from miles away
lots of very sharp teeth that are constantly replaced
Photo credit: © 2006 Jupiterimages Corporation
Teacher notes
A shark’s teeth are not fixed to its jaw but embedded directly into the flesh. Its teeth are constantly replaced as they fall out or are broken, so that a shark may get through thousands of teeth during its lifetime. The lower teeth are mainly used for holding prey, while the upper teeth are used for cutting.
The shark’s specialized sense organs include:
lateral lines – a row of fluid-filled sensory canals along each side of the shark. These can detect movement and changes in pressure from about 100m away.
ampullae of Lorenzini – small pits in the shark’s snout that detect tiny electrical fields, such as those associated with muscle contraction of prey.
auditory system – can detect the sound created by injured prey from over 1 mile away.
silver colouring underneath acts as camouflage

6. The importance of adaptation
Biology:
Adaptation
Why is it important that organisms are adapted to their environment?
The better adapted an organism is to its habitat, the more successful it will be when competing for resources such as food and mates.
This increases the organism’s chance of survival and so increases its chance of reproducing and passing on its genes.
Teacher notes
See the ‘Competition’ presentation for more information on competition and survival.

7. True or false? Biology: Adaptation Teacher notes
This true-or-false activity could be used as a plenary or revision exercise on adaptation, or at the start of the lesson to gauge students’ existing knowledge of the subject matter. Coloured traffic light cards (red = false, yellow = don’t know, green = true) could be used to make this a whole-class exercise.