Human Respiratory System Overview

Study Notes

Human Respiratory System

Functions to obtain oxygen and eliminate carbon dioxide through two phases: inspiration and expiration.
Inspiration refers to the inhalation process of taking in air, while expiration is the exhalation process of blowing out air.

Organs of the Respiratory System

Nose/Nasal Cavity: Warms, moistens, and filters incoming air; also referred to as external nares.
Pharynx: Serves as a passageway for the respiratory and digestive systems; commonly known as the throat; leads to the trachea.
Larynx: Contains vocal cords, known as the voice box.
Trachea: Keeps the windpipe open; lined with cilia that filter air before it reaches the lungs.
Bronchi: Two primary branches diverging from the trachea; lead into each lung.
Bronchioles: Smaller branches from the bronchi leading to lung tissue and ultimately alveoli.
Alveoli: Small air sacs within the lungs where gas exchange occurs.
Pleura: Protective membrane surrounding each lung.

Functions of the Respiratory Tract

Upper Respiratory Tract: Provides air passage, contains smell receptors, filters foreign materials, moistens and warms air, and acts as resonating chambers for voice.
Lower Respiratory Tract: Maintains open airway, appropriately routes food and air, assists in sound production, transports air to and from the lungs.

Processes of Respiration

Breathing: Involves air moving into and out of the lungs.
External Respiration: Refers to gas exchange between air and blood.
Internal Respiration: Involves gas exchange between blood and tissues.
Cellular Respiration: Uses oxygen to produce ATP, generating carbon dioxide as a waste product.

Diseases of the Respiratory System

Asthma: Severe allergic reaction causing tightness of bronchioles.
Bronchitis: Inflammation of the bronchial lining.
Emphysema: Deterioration of alveoli leading to loss of lung elasticity.
Pneumonia: Accumulation of fluid in alveoli, blocking gas exchange.
Lung Cancer: Characterized by irregular and uncontrollable cell growth in lung tissue.

Human Circulatory System

Transports nutrients and oxygen to cells and removes waste for excretion.
Maintains fluid balance and normal temperature in the body.
Acts as a defense mechanism against harmful pathogens.
Known as a closed transport system or internal transport system.

Heart Structure and Function

Heart: Muscular organ, fist-sized, located between lungs and behind the breastbone; surrounded by the pericardium protective membrane.
Heartbeat: Rhythmic contraction and relaxation of heart muscles for pumping blood.

Blood Composition

Blood comprises 45% blood cells and 55% plasma.
Plasma: Nonliving liquid portion, over 90% water, contains proteins, salts, and transported materials.
Fibrinogen: Protein in plasma essential for blood clotting.
Red Blood Cells (RBC): Transport gases (O2, CO2); also called erythrocytes, have a lifespan of 100-120 days, produced in the red marrow.
White Blood Cells (WBC): Defend against pathogens; larger and fewer than RBC, with a lifespan of 13-20 days. Two types: those with granules (neutrophils, eosinophils, basophils) and without (lymphocytes, phagocytes).
Platelets: Aid in clotting, preventing bleeding; known as thrombocytes, with a lifespan of 3-5 days.

Blood Types and Discovery

Discovered by Karl Landsteiner; involves antigens A and B on RBCs and corresponding antibodies anti-A and anti-B in serum.
Blood Types:
- Type A
- Type B
- Type AB: Universal recipient
- Type O: Universal donor
Blood-letting: Historical practice of drawing blood from a person.

Types of Blood Vessels

Arteries: Carry oxygen-rich blood away from the heart to tissues.

Description

Explore the essential functions of the human respiratory system, including the phases of respiration: inspiration and expiration. Learn about the key organs involved, such as the nasal cavity and pharynx, and how they contribute to breathing.