Body Systems
The body's circulatory system (血液循環(huán)系統(tǒng)) includes the heart and blood vessels (血管).
The heart pumps blood to all parts of the body through a network of arteries and veins (動脈和靜脈).
The digestive system (消化系統(tǒng)) breaks down (分解) and absorbs food (吸收食物) into the body.
It supplies the energy that the body needs for growth and repair (生長和修復).
After digestion, excess food (多余的食物) is turned into waste and eliminated from the body (被排出體外).
The nervous system (神經(jīng)系統(tǒng)) includes the brain, spinal cord (脊髓) and nerves (神經(jīng)).
This is your body's control system.
It controls your muscles and organs, including your circulatory and digestive system.
The respiratory system (呼吸系統(tǒng)) includes the nose and lungs.
It brings air and oxygen (氧氣) into the body and removes carbon dioxide (二氧化碳).
The lungs are where oxygen enters the bloodstream (血流), and carbon dioxide is removed.
The immune system (免疫系統(tǒng)) protects the body against infections (感染、傳染) and diseases (疾病).
Sneezing (打噴嚏) and fever (發(fā)燒) are examples of how the immune system works.
If an infection invades (侵襲，侵入) the body, the immune system attacks it.
Exercise:
1.— Which system circulates blood throughout the body?
? ?—?The heart pumps blood and the?blood vessels transport the blood?throughout the body.
2. —?Which system?digests food and?supplies energy to the body?
? ?—?the?digestive system
3.— Which system?brings air and?oxygen?into the body?
? ?— the?respiratory system
4.— What is?your body's control system?
? ?— the?nervous system
5.— Which body system protects the body against?infections?
? ?— the?immune system
6.?The heart pumps blood to all parts of the body through a network of
7. The?digestive system is where the food is broken down and absorbed?into the body.
8.?It brings air and?oxygen?into the body and removes?carbon dioxide.
Repeat & Read Sentences:
1.?The?respiratory system?includes the nose and lungs.
2.?It?brings?air and oxygen into the body and?removes?carbon dioxide.
3.?Sneezing?and?fever?are examples of how the immune system works.
4.?The body's?circulatory system?includes the heart and?blood vessels.
5.?The?digestive system?breaks down?and?absorbs food?into the body.
Great Discoveries
The controlled use of fire (控制和使用火) allowed people to cook food and survive (幸存) in colder climates.
Fire provided light so that people could work and socialize (參與社交) for longer hours.
With the invention of agriculture (農(nóng)業(yè)的發(fā)明), people could grow food and settle into communities (融入群體生活).
By growing food, people could spend less time hunting, and more time for other things such as art.
The domestication (馴養(yǎng)) of animals allowed people to raise and use animals for food and work.
By raising herds of animals (成群的動物) 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 (運輸).
The development of tools and machines has resulted in more efficient manufacturing (制造業(yè)) and construction (建筑業(yè)).
With better tools and machines, work can be done with fewer people and at much lower costs.
The development of science and engineering has improved many things, including communications.
With an understanding of electricity, telephones and radios allow people to communicate over long distances.
Exercise:
1.— What??allowed people to cook food?
? ?—?The?controlled use of fire?allowed people to cook food.
2.—?What has improved the quality and efficiency in manufacturing?and?construction?
? ?—?The development of tools and machines has resulted in more efficient?manufacturing?and?construction.
3.—?What allowed people to take advantage of the?strength of?animals?
? ?—?The?domestication?of animals allowed people to raise and use animals for food and work.
4.—?What helped people to spend less time?hunting for food?
? ?—?With the?invention of agriculture, people became less?dependent on?hunting for food.
5.—?What has changed the way we?communicate?
? ?—?Science and engineering have?changed the way we?communicate with each other.
6.?Fire provided light so that people could work and?socializefor longer hours.
7.?The strength of animals such as horses and oxen was used for work and
8.?With better tools and machines, work can be done with fewer people and at much lower costs.
Repeat & Read Sentences:
1.?With the?development of agriculture, people had more time for other activities.
2.?Science and engineering have?changed the way we?communicate with each other.
3.?The?controlled use of fire?allowed people to cook food and?survive?in colder climates.
4.?Science and engineering?breakthroughs are rapidly?changing the way we live our lives.
