Body Systems
The body's?circulatory?system includes the heart and blood?vessels.
The heart pumps blood to all parts of the body through a?network?of?arteries?and?veins.
The digestive system breaks down and absorbs food into the body.
It's supplies the energy that the body needs for growth and repair.
After digestion,?excess?food is turned into waste and eliminated from the body.
The?nervous?system includes the brain,?spinal cord?and nerves.
This is your body's control system.
It controls your?muscles and organs, including your circulatory and digestive systems.
The?respiratory?system includes the nose and lungs.
It brings air and oxygen into the body and removes carbon dioxide.
The lungs are where oxygen enters the bloodstream, and carbon dioxide is removed.
The?immune?system protects the body against infections and diseases.
Sneezing and fever are examples of how the immune system works.
If an infection invades the body, the immune system attacks it.
The blood vessels that carry oxygen-rich blood?from?the heart are called arteries.
The digestive system is where food is broken down and absorbed into the body.
The nervous system regulates your heartbeat and digestion.
Great Discoveries
The controlled use of fire allowed people to cook food and survive in the colder climates.
Fire provided light so that people could work and?socialize?for longer hours.
With the invention of?agriculture, people could grow food and?settle into communities.
By growing food, people could spend less time hunting, and more time for other things such as art.
The?domestication?of animals allowed people to raise and use animals for food and work.
By raising herds of animals such as sheep, humans had a regular supply of meat and clothing.
The strength of animals such as horses and?oxen?was used for work and transportation.
The development of?tools and machines has resulted in more efficient?manufacturing and construction.
With better tools and machines, work can be done with fewer people and at much lower costs.
The development of science engineering has improved many things, including communications.
With an understanding of electricity, telephones and radios allow people to communicate over long distances.
Science and engineering have changed the way we communicate with each other.
With the development of agriculture, people had more time for other activities.
The use of machines has reduced the number of people needed to make things.
The ability to raise herds of animals gave human a regular supply of meat and clothing.
