BIOS 255 Week 6 Respiratory System-Anatomy
Student Name
Chamberlain University
BIOS-255: Anatomy & Physiology III with Lab
Prof. Name
Date
Respiratory System – Anatomy
Learning Objectives
- Identify the main anatomical structures of the respiratory system.
- Trace the pathway of air through the respiratory tract during breathing.
- Apply Boyle’s Law to understand pressure and volume changes during breathing.
- Define and differentiate between the various lung volumes involved in respiration.
Introduction
The respiratory system plays a vital role in ensuring oxygen delivery to tissues and the removal of carbon dioxide from the body. The passage of air begins at the nasal or oral cavity, continues through the pharynx and larynx, and proceeds down the trachea into the branching bronchial tree before reaching the alveoli in the lungs. Inhalation is driven by the expansion of the thoracic cavity, which reduces intrapulmonary pressure below atmospheric levels, allowing air to flow inward. This is facilitated by the diaphragm and intercostal muscles. The lungs are enclosed within a double-layered pleural membrane that provides protection and helps maintain intrapleural pressure. Assessing pulmonary function through tools such as spirometry provides valuable insights into lung capacity and efficiency. Understanding these elements provides a foundation for exploring the intricate processes of respiratory physiology.
Assignment
Part 1: Anatomy.TV Activity
Students are required to complete the interactive modules on Anatomy.TV, covering:
- Upper and lower respiratory tract
- Pulmonary ventilation
- Lung volumes and capacities
Instructions to Access:
- Navigate to the Resources tab.
- Select Library > Library Resources – Database A-Z > Anatomy.TV.
- Choose the relevant system and topics as assigned.
- Review the educational material and complete the simulations and quizzes.
Respiratory Anatomy Lab Report
Purpose
This laboratory activity aims to explore respiratory physiology by examining the anatomical components of the respiratory system, understanding airflow mechanics, applying Boyle’s Law, and evaluating different respiratory volumes.
Procedure
The lab involves recognizing key structures of the respiratory system and tracing the flow of air from the upper respiratory tract into the alveolar sacs of the lungs. It includes interactive exercises, model labeling, and physiological concept applications.
Data and Observations
a. Functions of the Respiratory System
| Function | Description |
|---|---|
| Gas Exchange | Facilitates oxygen uptake and carbon dioxide removal through alveoli. |
| Pulmonary Defense Mechanisms | Traps particulates, pathogens, and filters air via mucociliary escalator. |
| Acid-Base Regulation | Maintains pH by balancing CO₂ levels through ventilation control. |
| Metabolic Processing | Involves inactivation and modification of bioactive substances. |
b. Anatomy of the Larynx
Key components in the laryngeal model include:
- Thyroid Cartilage – The large, shield-shaped cartilage forming the Adam’s apple.
- Cricoid Cartilage – A ring-like structure below the thyroid cartilage.
- Epiglottis – A flap-like cartilage that prevents food from entering the trachea during swallowing.
Questions and Explanations
a. What is Boyle’s Law and how does it apply to respiration?
Boyle’s Law states that the pressure of a gas is inversely related to its volume when temperature remains constant. During inhalation, the diaphragm contracts, expanding the thoracic cavity, which decreases the intrapulmonary pressure and draws air into the lungs. Conversely, exhalation involves diaphragm relaxation, reducing lung volume and increasing pressure, thus expelling air.
b. How does the thoracic cavity’s volume affect lung pressure?
The thoracic cavity’s expansion during inspiration lowers alveolar pressure relative to the external atmosphere, facilitating airflow into the lungs. During expiration, the cavity contracts, increasing pressure and pushing air out.
c. What role does surfactant play in lung function?
Surfactant is a phospholipid-rich substance secreted by alveolar cells. It reduces surface tension within alveoli, preventing collapse, especially during exhalation, and aids in keeping the alveoli open for effective gas exchange.
BIOS 255 Week 6 Respiratory System-Anatomy
d. What are the main pulmonary volumes?
| Pulmonary Volume | Description |
|---|---|
| Tidal Volume (TV) | Air moved in and out during normal breathing (~500 mL). |
| Inspiratory Reserve Volume | Additional air inhaled beyond a normal breath (~3000 mL in adults). |
| Expiratory Reserve Volume | Air forcefully exhaled after a normal breath (~1200 mL). |
| Residual Volume | Air remaining in lungs after maximal exhalation (~1200 mL). |
Discussion
a. What is anatomical dead space?
Anatomical dead space refers to portions of the respiratory tract (trachea, bronchi, bronchioles) where air flows but no gas exchange occurs. Typically, this volume is around 150 mL in a healthy adult and represents air that never reaches the alveoli.
b. Were there any difficulties experienced during the lab?
One challenge encountered was the rotation functionality of the digital skeleton model, which was not as intuitive. Improved interactivity and labeling features would enhance the learning experience.
Reflection
- Through this lab, I gained insights into the principles of ventilation and the mechanics of oxygen and carbon dioxide exchange.
- I discovered the importance of the carina, a cartilage ridge at the bifurcation of the trachea, which serves as a crucial anatomical landmark and sensitive area that triggers the cough reflex.
- Understanding these structures and processes will aid in clinical practice, especially when interpreting respiratory assessments or assisting with airway management.
Grading Rubric
| Component | Points |
|---|---|
| Part 1: Completion of Anatomy.TV modules | 10 |
| Part 2: Lab Report | |
| – Purpose | 2 |
| – Procedure | 2 |
| – Data and Observations | 5 |
| – Questions | 4 |
| – Discussion | 2 |
| – Reflection | 5 |
| Total | 30 |
References
American Lung Association. (2023). How lungs work. https://www.lung.org/lung-health-diseases/how-lungs-work
Marieb, E. N., & Hoehn, K. (2018). Human Anatomy & Physiology (11th ed.). Pearson.
BIOS 255 Week 6 Respiratory System-Anatomy
National Heart, Lung, and Blood Institute. (2022). Your lungs & respiratory system. https://www.nhlbi.nih.gov
OpenStax. (2020). Anatomy and Physiology. https://openstax.org/books/anatomy-and-physiology/pages/1-introduction