Respiratory System Overview Quiz

Respiratory System

• Breath represents life, the first breath of a baby and the last of a dying person are dramatic moments
• Breathing is necessary because metabolism requires ATP, which in turn requires oxygen and creates carbon dioxide
• The respiratory system is a tube system that delivers air to the lungs, where oxygen diffuses into the blood and carbon dioxide is removed
• It has more diverse functions, which include gas exchange, communication, olfaction (smell), acid-base balance, blood pressure regulation, and expulsion of abdominal contents

Main Function

• The respiratory system's main function is to deliver oxygen to the blood and remove carbon dioxide
• The system has three zones:
  • upper respiratory tract - which is from the nostrils through the pharynx (the throat)
    • nose - warms, cleanses, and humidifies inhaled air; detects odors
    • nasal septum separates right and left nasal cavities
    • two nasal fossae (right and left halves)
    • nasal conchae - superior, middle, and inferior turbinates which increase surface area for air warming, humidification, and cleaning -middle respiratory zone - which includes the larynx (the voice box), the trachea (the windpipe), bronchi, alveoli, and bronchioles -larynx- "voice box", keeps food out of lungs -trachea- The windpipe - supported by rings of cartilage -bronchi- are the right and left branches of the trachea -alveoli- are the extremely small air sacs that are the site of gas exchange -bronchioles - a series of progressively smaller branches leading to the alveoli
  • lower respiratory tract- which is from the trachea into the bronchi and their subdivisions
    • The bronchi undergo repeated branching, decreasing in diameter, becoming bronchioles. -Bronchioles terminate in tiny air sacs called alveoli

Conducting Zone

• The conducting division of the respiratory system
• Carries air
• No gas exchange
• From nostrils to bronchioles

Respiratory Zone

• The respiratory division of the respiratory system
• Gas exchange site
• Alveoli

Nose (Nasus)

• Warms, cleanses, and humidifies inhaled air
• Detects odors in the airstream
• A resonating chamber that amplifies the voice
• Extended from anterior openings (nostrils or nares) to posterior openings (posterior nasal apertures or choanae)

Pharynx (Throat)

• Muscular funnel extending from the base of the skull to the level of the cricoid cartilage
• Three regions:
  • Nasopharynx - behind nasal cavity
  • Oropharynx - behind oral cavity
  • Laryngopharynx - near larynx

Larynx

• Cartilaginous chamber that keeps food and drinks out of the airway, and has an additional role in sound production (phonation)
• A flap of tissue called the epiglottis
• The superior opening is guarded by a flap of tissue called the epiglottis

Trachea and Bronchi

• The trachea (windpipe) is a tube about 12 cm long and 2.5 cm in diameter
• Supported by 16-20 C-shaped rings
• Branches into the right and left bronchi
• Bronchi undergo repeated branching, and decrease in diameter, becoming bronchioles.

Lungs

• Right lung has three lobes(superior, middle, inferior)
• Left lung has two lobes (superior, inferior)
• The lobes are separated by fissures.
• The place where the structures enter and exit the lung is called the root of the lungs (hilum)

Pleura

• A double-layered membrane that surrounds the lungs
  • Visceral pleura - covers the lungs
  • Parietal pleura - lines the thoracic cavity
• Space between the pleural layers is called the pleural cavity
• Contains serous fluid to reduce friction during breathing