Respiratory System Grade 10

Respiratory System

The body system responsible for bringing oxygen into the body and removing carbon dioxide. It works closely with the circulatory system to deliver oxygen to cells and remove waste gases.

Nasal Cavity

The space inside the nose where air enters the respiratory system. It warms, moistens, and filters the air before it travels deeper into the lungs.

Mouth

An alternate pathway for air to enter and leave the respiratory system. It can be used for breathing when the nasal passages are blocked or during increased breathing demands.

Pharynx

The throat area that serves as a passageway for air moving from the nose or mouth toward the larynx. It is shared by both the respiratory and digestive systems.

Larynx

Also called the voice box, the larynx connects the pharynx to the trachea. It contains the vocal cords and helps protect the airway.

Trachea

Also called the windpipe, the trachea carries air from the larynx toward the bronchi. Cilia and mucus help trap particles and germs in the airway.

Bronchi

The two main branches of the trachea that carry air into the right and left lungs. They continue dividing into smaller airways called bronchioles.

Bronchioles

Small branches of the bronchi that carry air deeper into the lungs. The smallest bronchioles end in clusters of alveoli where gas exchange occurs.

Alveoli

Tiny, hollow air sacs at the ends of the smallest bronchioles where gas exchange takes place. Oxygen diffuses into nearby capillaries while carbon dioxide diffuses out of the blood.

Lungs

The main organs of the respiratory system where oxygen and carbon dioxide are exchanged. The right lung is slightly larger than the left lung.

Diaphragm

A large muscle located beneath the lungs that helps control breathing. When it contracts, the lungs expand and air is drawn in; when it relaxes, air is pushed out.

Cilia

Tiny, mucus

Inhalation

The process of breathing air into the lungs, bringing oxygen into the body. The diaphragm contracts and moves downward, allowing the lungs to expand.

Exhalation

The process of breathing air out of the lungs, removing carbon dioxide from the body. The diaphragm relaxes and the lungs decrease in volume.

External Respiration

Gas exchange between the air in the alveoli and the blood in nearby capillaries. Oxygen enters the blood while carbon dioxide leaves it through diffusion.

Internal Respiration

Gas exchange between the blood and the cells of the body. Oxygen moves from the blood into cells, while carbon dioxide moves from cells into the blood.

Diffusion

The movement of particles from an area of high concentration to an area of low concentration. It allows oxygen and carbon dioxide to move between the alveoli, blood, and body tissues.

Tuberculosis (TB)

An infectious disease caused by bacteria that can enter the body through breathing. The bacteria can grow in the lungs and may become serious or fatal if untreated.

Lung Cancer

A disease in which abnormal cells grow uncontrollably in the lungs or other parts of the respiratory system. Tobacco smoke contains carcinogens that can increase the risk of lung cancer.

SARS

Severe Acute Respiratory Syndrome is a respiratory illness caused by a virus. Symptoms can include fever, dry cough, shortness of breath, sore throat, headache, muscle pain, and exhaustion.