Upper Respiratory System Quiz

Upper Respiratory System

• Nasal Cavity: Warms, moistens, and filters inhaled air. Holds olfactory receptors for smell. Unlike the mouth, air entering the nasal cavity is filtered, warmed, and moistened.
• Pharynx: A common passageway for air, food, and water. Connects the nose, mouth, and throat. Part of both the respiratory and digestive systems.
• Larynx (Voice Box): Houses the vocal cords, enabling sound production. Located in the middle of the neck, behind the esophagus.
• Epiglottis: A flap of cartilage that covers the trachea (windpipe) during swallowing to prevent food from entering the lungs. It stays open during breathing to allow air into the larynx.
• Trachea (Windpipe): A tube that carries air from the upper respiratory tract to the lungs. Lined with goblet cells that produce mucus. Cilia sweep trapped particles away. Cartilage rings provide structural support to maintain an open pathway. The trachea's rigid structure contrasts with the esophagus's collapsible nature.

Lower Respiratory System

• Bronchi: Branches from the trachea, with cartilage rings for structural support. They decrease in size as they branch into smaller tubes.
• Bronchioles: The smallest branches of the bronchi, lack cartilage rings, and are susceptible to collapse with damage, smoking.
• Alveoli: Tiny air sacs in the lungs where gas exchange occurs (oxygen and carbon dioxide). Their thin walls facilitate rapid diffusion. Susceptible to damage from smoking, without them, gas exchange is impaired, leading to rapid fatigue. Alveoli contain fluid, which can cause edema if damaged.
• Diaphragm: A large, dome-shaped muscle that contracts to expand the chest cavity, drawing air into the lungs. Relaxes to expel air. Lies under the ribs.
• Intercostal Muscles: Muscles between the ribs, assist in expanding and contracting the rib cage during breathing.
• Pleural Membrane: Forms an airtight sac around the lungs, crucial for proper inflation and deflation. The pressure within this cavity allows efficient lung function. A punctured pleural cavity disrupts this pressure, leading to lung collapse.

Cells of the Respiratory System

• Ciliated Cells: Line the trachea and bronchi. Cilia sweep away trapped dust and pathogens.
• Goblet Cells: Produce mucus, trapping foreign material. The mucus produced can expand significantly when needed. Excessive mucus production, however, can lead to respiratory problems.