Diversity of Living Things
Life Systems - Grade 6
Needs and Characteristics
Characteristics of Living Things
- Made up of cells
- Uses energy
- Reproduce
- Can adapt
- Respond to surroundings
- Grow and Develop

What are Life Processes?
Life processes are the things an organism must do to stay alive. Living things carry out all life processes which include: Ingestion, Digestion, Respiration, Excretion and Transport.
Ingestion - taking in food
Digestion - breaking food down so it can be used
Respiration - getting energy from food
Excretion - getting rid of waste
Transport - moving nutrients and   waste

Reproduction: Reproduction is the process where living things produce new organisms (offspring) like themselves. Two Types of Reproduction are Asexual Reproduction - reproduction needing only one parent, and Sexual Reproduction - reproduction needing two parents

Food and Water: Food is necessary for growth and energy. Plants and animals cannot survive without water. Water is used to transport nutrients and wastes through living things. Water is necessary to carry out chemical changes in living things.
Air: Air is a mixture of gases,one of which is oxygen. Oxygen is used by many living things to change food into energy. Land organisms get oxygen from the air whereas water organisms get oxygen from water.

What Do Living Things Need?
Living Space

Adaptations: An adaptation is a trait of a living thing that helps it live in its environment.  Adaptations make each living thing suited to life in its environment.  For example cactuses have thick leathery stems to store water and help them survive in the desert and polar bears have thick fur and layers of fat to survive in the cold.
Response: A Response is when a living thing reacts to stimuli and stimuli is a change in your surroundings. All living things respond to stimuli. The ways in which living things respond is called behaviour. Bird's migrating to warm places is a response and hibernation (sleeping) through the winter months is another response.
Temperature: Proper temperature is necessary for living things to carry out life processes. Many living things would die without homeostasis. Homeostasis is the ability of a living thing to keep conditions inside its body constant. It  keeps life processes working even if external temperature changes
Living Space: Living space includes air, water, sunlight, food, and shelter. Organisms need living space to survive and most often have to compete for it.
The Animal Kingdom  (see diagram)
In the Animal Kingdom we can find two main groups, vertebrates (with a backbone) and invertebrates  (without a backbone).  The vertebrates include fish, amphibians (frogs), reptiles, birds and mammals. The invertebrates include molluscs (snails), worms , arthropods (spiders), sponges, echinoderms (starfish), cnidarians (jellyfish, coral) and a few others. Now, let's take a closer look at these two main groups.


Vertebrates, animals with backbones, have endoskeletons, their skeletons on the insides of their bodies. Examples of animals with their backbones inside their bodies are:birds, mammals, reptiles, fish and amphibians.  Vertebrates can either be warm-blooded or cold-blooded. What does all this mean? Warm-blooded means that the animal's body temperature is always the same, unless of coarse the animal gets sick. All mammals are warm-blooded as are birds. Warm-blooded animals keep their body temperature constant and this can take a lot of energy for them to keep warm. That is why you should wear a hat in the cold weather - to help keep in body heat. On the other hand, cold-blooded animals do not have to worry about using up energy to keep warm. Thses animals adapt to their environment - their body temperature is the same as their surroundings. Fish, reptiles and amphibians are examples of cold-blooded animals.

Fish, amphibians, mammals, birds, reptiles - VERTEBRATES -  with endoskeletons - some warm-blooded, some cold-blooded.

It's time to take a closer look at these vertebrates.

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Science Hompage
Grade 6
Characteristics of birds, reptiles, fish, amphibians and mammals
( pdf files from Reptilians.org )
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