🫁 Respiratory System
This is the main organ where gas exchange occurs.
Lungs
This organ pumps blood throughout the body.
Heart
The respiratory system brings this gas into the body for cells to use.
Oxygen (O2)
The function of this organ is to pump blood.
Heart
You take a deep breath. Which system is directly responsible for bringing air into your lungs?
respiratory system
Air travels through this tube after passing through the pharynx and before reaching the bronchi.
Trachea
These blood vessels carry blood away from the heart.
Arteries
The circulatory system transports oxygen from the lungs to this destination.
body cells
The function of the diaphragm is most directly related to this process.
Breathing
Your heart beats faster while running. What is the main reason your body does this?
To circulate blood more quickly and help deliver needed oxygen to cells.
These tiny air sacs are surrounded by capillaries and are the main location of gas exchange.
alveoli
These tiny blood vessels allow materials to move between the blood and body cells.
capillaries
The respiratory system removes this waste gas from the body.
Carbon Dioxide (CO2)
The structure that separates the left and right sides of the heart helps prevent this.
mixing of oxygen-rich and oxygen-poor blood
You hold your breath for a long time. Which waste gas begins building up in your body?
carbon dioxide (CO2)
This muscle contracts and moves downward to help pull air into the lungs.
diaphragm
These blood vessels carry blood back toward the heart.
Veins
A student runs around the playground. Explain how the respiratory and circulatory systems work together to help the student's cells.
The respiratory system brings oxygen into the lungs. Oxygen enters the blood, and the circulatory system carries it to cells. The blood also carries carbon dioxide from cells back to the lungs so it can be removed.
Why are blood vessels with thick, muscular walls useful for carrying blood away from the heart?
They can withstand the high pressure of blood being pumped from the heart.
You sprint up a flight of stairs. Your breathing and heart rate both increase. Why do BOTH systems respond?
Your cells need more oxygen and produce more carbon dioxide during increased activity.
Explain why the alveoli are well suited for gas exchange.
They have thin walls and are surrounded by many capillaries, allowing oxygen and carbon dioxide to diffuse efficiently.
Why are capillaries important to the circulatory system?
They are the tiny vessels where substances such as oxygen, carbon dioxide, nutrients, and wastes can move between blood and body cells.
A student's muscles need more oxygen during exercise. Explain what happens in BOTH systems to meet this need
Breathing increases so more oxygen enters the lungs. The heart beats faster to circulate oxygen-rich blood to the working muscles. Carbon dioxide produced by the cells is transported back to the lungs for removal.
A student's alveoli become damaged. Predict how this could affect the circulatory system.
Less oxygen may enter the blood, so the circulatory system has less oxygen to deliver to body cells.
Put these events in the correct order:
1. Oxygen enters the lungs →
2. Oxygen moves into the blood →
3. Blood transports oxygen →
4. Oxygen reaches body cells