Respiratory Anatomy

Respiratory Anatomy

• The nasal cavity
• Thoracic cavity
• the trachea
• bronchi (primary, secondary and tertiary)
• bronchioles (terminal and respiratory)
• Alveoli
• Diaphragm

Respiratory Physiology

• providing gas exchange for the body (O2 in and CO2 out)
• Regulation of blood pH
• Speech
• immune system - defense against microbes (cilia in conduction zone)
• chemical messenger concentrations
• trapping and dissolving blood clots

• The conducting zone – brings air into lungs, “conducts” the air.
• from the trachea to the tertiary bronchi
• The respiratory zone – site of gas exchange
• from the bronchioles to the alveoli

Upper Respiratory Anatomy

The Nose

• Air taken into the nose is heated and moistened before moving into the pharynx
• Tiny hairs that line the nose trap and block large particles (like dirt and dust) from entering the body
• Mucus lines the outside of the cell of the nasal cavity to block microscopic particles (dust, bacteria, viruses) from entering the body

The Pharynx

• Air moves into the pharynx from either the nose or the mouth before moving into the larynx and trachea
• Food also passes through the pharynx before moving into the esophagus
• The epiglottis stops food from entering the trachea
• Cartilage of the larynx supports the epiglottis

The Larynx

• Cartilage and ligaments at the top of the trachea form the larynx
• Air moves into the larynx before traveling down the trachea to the bronchi
• The larynx contains the vocal cords
• Vocal cords vibrate when air is pushed out of the lungs, different rates of vibrations gives different sounds
• Human males after puberty have a an increase in the size of the cartilage that protects the voice box (the Adam's apple) that causes lower frequency vibrations

• Cilia help clear the lungs
• Mucus helps protect the lungs
• Columnar epithelial cells are durable and sturdy

Respiratory Zone

• No mucus or cilia!
• Thin (squamous) epithelial cells for gas exchange

Alveolar Anatomy and Function

1. Macrophage cells
2. Type ll cells
3. Type l cells
4. Capillaries

• Alveoli are good at exchanging gases because
• they have a thin membrane
• they have a super high surface area
• they have a high pressure gradient for gas exchange
• 
  
• $Rate\ of\ Diffusion\ =\ \frac{gradient\left(SA\right)}{thickness}$