Respiratory System Anatomy Quiz

Upper Respiratory Tract Structures and Functions

• Pharynx connects the oral to the nasal passage for both air and food
• Epiglottis covers the windpipe to ensure food passes into the oesophagus
• Larynx (voice box) contains vocal cords that vibrate when air passes through for sound production

Lower Respiratory Tract Structures and Functions

• Trachea (windpipe) is a muscular pipe surrounded by C-shaped cartilage for strength and flexibility
• Bronchus (right and left) and bronchioles have smooth muscles
• Alveoli are the basic units of the respiratory system where gas exchange occurs

Branching of Airways and Zones

• Conducting zone: from nose to terminal bronchioles, responsible for warming, humidification, and filtration of air
• Respiratory zone: includes respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli, where gas exchange occurs

Protective Mechanisms in the Respiratory System

• Ciliated epithelium in trachea and bronchi: warms and humidifies the air, and filters out foreign particles
• Mucus containing immunoglobulins disables pathogens
• Phagocyte cells (pulmonary alveolar macrophages, lymphocytes, plasma cells) engulf inhaled particles and bacteria

Alveoli and Gas Exchange

• Alveoli are the actual sites of gaseous exchange between the lungs and blood
• Each alveolus has a thin membrane for easy exchange of gases with capillaries
• Diffusion occurs between the alveoli and capillaries for gas exchange

Respiration Process

• Movement of air into and out of the lungs (breathing or ventilation)
• Gas exchange between the alveolar air and the blood in the lungs (external respiration)
• Gas transport in the blood between the lungs and body cells
• Gas exchange between the blood and the cells in the systemic capillaries of the body (internal respiration)
• Oxygen utilization and carbon dioxide production at the cellular level (cellular respiration)