The Respiratory System Quiz

The Respiratory System

• Respiration is a complex process involving four main steps:
  • Exchange of air between the atmosphere and lungs (breathing).
  • Exchange of oxygen (O2) and carbon dioxide (CO2) between the lungs and blood.
  • Transport of O2 and CO2 by the blood.
  • Exchange of gases between blood and the cells.

Respiration Objectives

• Discuss the process of respiration.
• Understand the functional organizations of the respiratory system.
• Identify the functions of respiratory system structures.
• Discuss asthma as an example of a homeostatic imbalance.
• Identify the components of the respiratory membrane.
• Understand the physical properties of the lungs.
• Discuss the mechanics of breathing.
• Discuss modified breathing movements.

Respiration Types

• Cellular respiration: A metabolic process within the cell's mitochondria to produce energy (ATP).
• External respiration: Exchange of gases between the atmosphere & lungs.
• Internal respiration: Exchange of gases between the blood and body cells

The Journey of Air Through the Respiratory System

• Nose and Nasal Cavity:

  • Warms, filters, and moistens inhaled air.
  • Hairs and mucous membranes filter.
  • Blood vessels in nasal capillaries warm air.

• Pharynx:

  • Passageway for air and food.
  • Three regions: nasopharynx, oropharynx, laryngopharynx.
  • Helps in speech sound resonance.

• Larynx (Voice Box):

  • Connects the pharynx to the trachea.
  • Prevents ingested materials from entering the respiratory tract (epiglottis).
  • Produces sound for speech.

• Trachea:

  • Connects the larynx to the bronchi.
  • Supported by C-shaped cartilaginous rings for structural strength and flexibility.
  • Contains goblet cells which produce mucus to trap particles and pathogens
  • Contains cilia that sweep inhaled particles upwards towards the throat.

• Bronchi:

  • Two main branches, right and left, leading into the lungs.
  • Cartilage provides support.
  • Divides into smaller branches as they enter the lungs, eventually becoming bronchioles.

• Bronchioles:

  • No cartilage, but have smooth muscle for dilation/constriction.
  • Regulates the amount of air reaching alveoli.

• Alveoli:

  • Tiny air sacs where gas exchange occurs.
  • Surfactant-coating prevents collapse.
  • Form the respiratory zone.

Respiratory Membrane

• Consists of alveolar epithelium, capillary endothelium, and fused basement membranes.
• Allows for efficient gas exchange (O2 into blood, CO2 out of blood).

Asthma

• Asthma: Chronic respiratory disease causing airway inflammation, bronchoconstriction, and mucus secretion.
• Triggers: Environmental factors (dust, pollen), changes in weather, mold, tobacco smoke, respiratory infections, exercises

Lung Structure/Function

• The right lung has three lobes (superior, middle, inferior).
• The left lung has two lobes (superior, inferior).

Physical Properties of the Lungs

• Compliance: How easily the lungs expand under pressure.
• Elasticity: Tendency of the lungs to return to their initial size after being stretched.

Mechanics of Inspiration and Expiration

• Air flow is based on pressure differences.
• Breathing involves changes in thoracic volume to alter pressure
• Inhalation increases thoracic volume, decreasing alveolar pressure, drawing air into the lungs.
• Exhalation decreases thoracic volume, increasing alveolar pressure, expelling air from the lungs.

Pulmonary Fibrosis

• A condition where lung tissue becomes scarred and stiff.
• Decreased lung compliance.

Modified Breathing Movements

• Crying: Involves convulsive exhalations with specific facial expressions.
• Laughing: Also involves inhalation followed by exhalations but with different rhythm & expressions.
• Yawning and Sighing: Other types of modified breathing.

Smoking and the Lungs

• Smoking causes emphysema.
• Emphysema: Lung disease characterized by damaged alveoli, loss of elasticity, and difficulty breathing.
• Smoking inhibits tissue regeneration in lungs

Surfactant and Premature Babies

• Pulmonary surfactant is a substance produced in the alveoli to prevent collapse.
• Premature babies may not produce enough surfactant, causing respiratory distress syndrome.
• Treatment involves exogenous surfactant administration.