Pharm 111 Week 1 Class Notes

Introduction to Respiratory System

Emphasis on understanding the lungs and gas exchange at a cellular level. Acknowledgment of the complexity of the PowerPoint presentation (over 60 slides). Key points will be provided for students, but reliance on them is discouraged as they won't cover everything necessary for exams.

Importance of Additional Information for Quizzes:

Due to the intricate nature of the respiratory system and the variety of processes involved, students must seek deeper knowledge beyond the outlined key points. Engaging in active reading, studying supplementary materials (such as textbooks and research articles), participating in discussions, and utilizing multimedia resources can greatly enhance understanding. It is also beneficial to review diagrams and models of the respiratory system to visualize structures and functions critically. Familiarity with terminology and concepts related to gas exchange and the physiological roles of different components of the respiratory system is vital.

Developing a comprehensive understanding will prepare students not only for quizzes but also for practical applications in clinical or advanced academic settings. For effective quiz preparation, students should practice explaining processes in their own words, as this reinforces learning and highlights areas that may need more attention.

Objectives of the Respiratory System

Requirements for Efficient Respiratory System:

Beyond just air movement; cells require energy for maintenance, growth, defense, and reproduction. Aerobic respiration: cells obtain energy by consuming oxygen (O2) and produce carbon dioxide (CO2).

Atmospheric Composition:

Atmospheric air consists of approximately 21% oxygen, nitrogen, CO2, and trace gases.

Gas Exchange Process:

Breathing involves inhaling O2 and exhaling CO2; essential for metabolic functions.

Structure of the Respiratory System

Components:

Divided into two main portions: conducting and respiratory.

Conducting Portion:

Includes structures such as the nose and airways that guide air to the lungs.

Respiratory Portion:

Site of gas exchange, primarily occurs in the alveoli.

Functions of the Respiratory System

Ventilation:

Defined as the movement of air in and out of the lungs. Crucial for maintaining airflow but does not directly imply gas exchange.

Protection Mechanisms:

Traps and eliminates pathogens and debris (e.g., dust).

Gas Exchange:

External respiration: gas exchange between lungs and bloodstream. Internal respiration: gas exchange within the tissues of the body.

The Process of Gas Exchange

External vs Internal Respiration:

• External Respiration: O2 exchanged from alveoli into capillaries, CO2 transferred back to be exhaled.

• Internal Respiration: O2 delivered from blood to the body's tissues, CO2 carried back to lungs.Importance of a large surface area in lungs for efficient gas exchange via numerous alveoli.

Life Functions Related to Respiratory System

• Ventilation: First step; moving air into the lungs.

• Oxygenation: Transferring oxygen to the bloodstream.

• Circulation: Moving oxygenated blood throughout the body.

• Perfusion: Delivering oxygen to tissues effectively.

Anatomical Structure of Respiratory System

Major Components:

• Nose: initiates air conduction and filtration.

• Pharynx, larynx, trachea: pathways for air to the lungs.

• Bronchi and bronchioles: further divide to reach alveoli.

• Alveoli: Small air sacs where the exchange of O2 and CO2 occurs. Surrounded by a capillary network to facilitate gas exchange.

Conducting Airways Functions

Air Filtering:

The respiratory system filters, warms, and humidifies air to protect lung tissues.

Respiratory Mucosa:

Lines the conducting portion; consists of mucous membranes and ciliated columnar epithelium. Produces mucus to trap debris and pathogens, protecting the airway.

Cilia Function in Airway Protection

Cilia: small hair-like structures that sweep mucus and trapped particles towards the throat for expulsion. Harmful effects of smoking on the function of cilia, reducing their ability to clear debris.

Upper and Lower Respiratory Tract Anatomy

Upper Respiratory Tract:

Nose, nasal cavity, pharynx;

Lower Respiratory Tract:

Larynx, trachea, bronchi, bronchioles, and alveoli.

Nasal Cavity:

Nasal conchae create turbulence to trap smaller particles.

Pharynx:

Divided into nasopharynx, oropharynx, and laryngopharynx; aids in both air and food passage.

Larynx:

Contains the epiglottis and vocal cords; plays a role in voice production and protects airways during swallowing.