Week 9 - Characteristics of Living Things

3 Structure and Function

Lesson 3

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for this lesson

Lesson 3: Structure and Function

Background Information All living organisms are systems composed of subsystems (lesson 2). All living organisms need to carry out the same basic life functions (lesson 1). However each type of plant or animal has a different system for caring out these life functions depending on their environment and surroundings. These different systems are called adaptations. For example: movement The following are all systems developed by animals to move around in their environment.

Adaptation for movement
Humans have 2 legs for walking
One theory as to why humans walk on two legs is that they have a strong need to communicate. It is easier to communicate with each other while standing on two legs.
Dogs, cats (and others) have 4 legs
Four legs lets animals move faster when hunting or chasing prey (or running away).
Fish have fins for swimming
The narrow flat design of fins helps push the fish through the water.
Birds have wings for flying
Birds wings are light, strong and aerodynamic for moving through the air.
Exercise 1.3: Structure and Function

Check Your Understanding 

The Background Information of Lesson 3 provided a chart with the adaptations that these creatures have for movement. A similar chart follows. Consider the 5 different living organisms below (plants, animals or insects) and identify how they have adapted for gathering food. Use the Internet to search for pictures and information.

Adaptation for Gathering food
Image of Organism
Explanation of Adaptation 
Always answer in complete sentences! 
Baleen whales
ant eater
Venus fly trap


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