Teacher: ______Period: ______
The Respiratory System
The respiratory system brings oxygen from the air into the blood and returns carbon dioxide from the blood to the air. The respiratory system works very closely with the circulatory system to provide cells with oxygen, and to remove waste carbon dioxide produced by the activities of cells.
1. The main function of the respiratory system is to______
______.
Directions: Trace the pathway of air on the diagram as you read the passage below. Follow the directions to make a color key for the respiratory system.
When you breathe, air enters the respiratory system through the nose. The lining of the nose produces mucus, which moistens air and traps germs and dirt and is lined with hairs to remove dust and dirt from the air.
2. What is a common name for mucus?______
3. What is the function of mucus in the nose?______
Air from the nose travels to the throat, and then goes through the trachea or windpipe. A flap called the epiglottis covers the windpipe to prevent food and water from entering the trachea.
4. Describe the function of the epiglottis______
The trachea branches off into two smaller tubes called bronchi, which lead to a lung through smaller and smaller branches called bronchioles.
The air then enters the tiny air sacs called alveoli where the blood picks up oxygen and then gets rid of carbon dioxide.
5. The tiny sacs in the lungs where oxygen and carbon dioxide enter and leave the lungs are called ______.
The lungs do not take in air by themselves. Breathing is caused by the actions of muscles in the ribs, diaphragm, and abdomen to draw in oxygenated air by making the chest cavity larger. As the chest cavity gets larger, the air pressure gets lower inside the chest and lungs. Air rushes into the lungs to equalize the air pressure. We breathe out carbon dioxide when the ribs move in and the diaphragm moves upward. This makes the chest cavity smaller which forces out of the lungs because of the increase in air pressure. All of these actions take place without us thinking about it, because breathing is an involuntary action controlled by the nervous system.
6. Muscle contractions in the ______, ______and ______cause us to breathe in and out.
7. Another word for breathe in is ______.
8. Another word for breathe out is ______.
Once in the lungs, the oxygen in the air passes across the thin membranes of the alveoli sacs in the lungs, and into the alveoli sacs in the lungs, and into the oxygen-poor blood in the tiny capillaries that surround the sacs. The thin-walled capillaries are so narrow that they can hold red blood cells in a single line.
9. Alveoli sacs are surrounded by ______which are so narrow (thin) they can hold______.
Circulatory System Cloze Passage
Directions: Complete the blanks with the word bank below each paragraph.
The ______system works closely with the respiratory, digestive and excretory systems to ______nutrients to the cells all over the body and remove ______from cells in all parts of the body. The ______, ______and ______are the three main parts of the circulatory system. Each part has specific structures to help perform the function of transporting______within the body.
Materials circulatory blood wastes deliver heart blood vessels
The ______is a fist-sized muscular organ that beats 70-80 times per minute. Each time your heart beats, it ______about ¼ cup of ______. Each minute it pumps 5 quarts of blood. The heart’s special ______allows it to receive ______poor blood from the body, pump the blood to the ______to pick up oxygen, and then pump ______rich blood back out to the body with each beat.
Heart oxygen beats lungs blood structure oxygen
The main ______of the ______system is to______throughout the body.
Transport Function circulatory materials