Respiratory System Quiz

Respiratory System

• Breath represents life, the first breath and last gasp are dramatic moments
• Breathing is crucial for metabolism, which requires ATP
• ATP synthesis needs oxygen and produces carbon dioxide; breathing provides oxygen and eliminates carbon dioxide
• The respiratory system's primary function is to deliver air to the lungs, allowing oxygen to enter and carbon dioxide to exit the blood

Main Function

• The respiratory system is an organ system responsible for supplying the blood with oxygen and removing carbon dioxide from it
• It has additional functions like communication (speech), olfaction (sense of smell), acid-base balance, blood pressure regulation, and expulsion of abdominal content

Parts of the Respiratory System

• Upper Respiratory Tract: Nose, nasal cavity, pharynx, larynx
• Lower Respiratory Tract: Trachea, bronchi, bronchioles, lungs, alveoli

Nose (Nasus)

• Warms, cleanses, and humidifies inhaled air
• Detects odors
• Resonating chamber for amplification of voice
• Anterior openings = nostrils / nares; Posterior openings = choanae

Pharynx (Throat)

• Muscular funnel extending from the choanae to the larynx (about 13cm)
• Has three regions:
  • Nasopharynx (superior)
  • Oropharynx (middle)
  • Laryngopharynx (inferior)

Larynx (Voice Box)

• Cartilaginous chamber (about 4 cm long)
• Keeps food and drink out of the airway
• Produces sound (phonation)
• Epiglottis – flap of cartilage that closes the airway during swallowing

Trachea and Bronchi

• Trachea (windpipe), a tube (about 12 cm long and 2.5 cm in diameter)
• Supported by C-shaped hyaline cartilage rings
• Branches into two primary bronchi
• Bronchi subdivide into smaller bronchioles
• Bronchioles terminate in alveoli (air sacs) within the lungs

Lungs

• Paired organs; three lobes on the right, two on the left
• Surrounded by pleura (membranes)
• Contains millions of alveoli, which facilitate gas exchange
• The root of the lung is where the main bronchus, blood vessels, lymphatic vessels, and nerves enter or exit the lung.
• Hilum - the indented area on the mediastinal surface where these structures pass through

Pleura

• Two-layered serous membrane surrounding the lungs
  • Visceral pleura: adheres to the lung tissue
  • Parietal pleura: lines the thoracic cavity
• Pleural cavity: potential space between the visceral and parietal pleura, containing a serous fluid that reduces friction during breathing

Gas Exchange

• Oxygen from inhaled air diffuses into the blood, and carbon dioxide from the blood diffuses into the alveoli to be exhaled