Respiratory System Anatomy

Study Notes

Respiratory tract comprises two main systems:
- Conducting system: Includes nasal cavity, sinuses, larynx, trachea, bronchi, and bronchioles.
- Exchange system: Primarily involves lungs and alveoli.

Mucosa consists of pseudo-stratified ciliated epithelium with goblet cells, which produce mucus.
Submucosa is composed of connective tissue that contains glands and blood vessels.

Hosts a normal population of bacteria that are typically harmless unless stressed by factors such as viruses.
Example includes Mannheimia haemolytica, which causes "Shipping Fever" in cattle.

Escape of blood from cardiovascular system can occur as external or internal bleeding.
Reactions in living tissue involve vascular changes and cellular responses to local injury.

Exudate: Fluid leaking from blood vessels, comprising cells, proteins, and solids.
- Catarrhal exudate: Mainly mucus with few inflammatory cells; associated with mucous membrane inflammation.
- Fibrinous exudate: Composed primarily of fibrin; indicates acute and severe inflammation, often adhering to surfaces.
- Purulent exudate: Rich in pus from dead neutrophils, indicates infections; can form abscesses (localized) or cellulitis (diffuse).
- Caseous exudate: Associated with chronic inflammation, containing cheesy necrotic material, predominantly macrophages, and giant cells.

Inflammation can be classified by duration:
- Peracute
- Acute
- Subacute
- Chronic (including chronic-active).

Granulocytes:
- Neutrophils: Key players in acute inflammation.
- Eosinophils: Involved in allergic responses and parasitic infections.
Agranulocytes:
- Lymphocytes: Important for adaptive immunity.
- Plasma cells: Produce antibodies.
- Macrophages: Involved in phagocytosis and tissue repair.
- Giant cells: Formed in response to chronic irritation, encapsulate foreign material.