GNM 1st Year | Anatomy & Physiology
Important examination questions and answers on the respiratory system, covering respiratory organs, lungs, breathing, gas exchange and regulation of respiration.
Important Questions & Answers on Respiratory System
The respiratory system is an important topic in GNM 1st Year Anatomy and Physiology. The questions below are arranged according to common nursing examination patterns to help students prepare structured answers and revise the chapter efficiently.
Long Answer Questions – 10 Marks
1. Define the respiratory system. Describe its main organs and functions.
Answer:
The respiratory system is a group of organs and structures that conduct air into and out of the lungs and allow the exchange of oxygen and carbon dioxide between the air and blood.
Main organs and structures include:
- Nose and nasal cavity
- Pharynx
- Larynx
- Trachea
- Bronchi
- Bronchioles
- Lungs
- Alveoli
Major functions:
- Brings oxygen into the body.
- Removes carbon dioxide.
- Provides the site for gas exchange.
- Helps maintain acid-base balance.
- Participates in voice production.
- Helps condition inspired air by filtering, warming and humidifying it.
2. Describe the structure of the lungs and explain their functions.
Answer:
The lungs are the main organs of respiration and are located in the thoracic cavity on either side of the mediastinum.
Right lung:
The right lung has three lobes: superior, middle and inferior.
Left lung:
The left lung has two lobes: superior and inferior. It is slightly smaller because of the position of the heart.
The lungs are covered by a serous membrane called the pleura. The visceral pleura covers the lung surface, while the parietal pleura lines the thoracic cavity.
Functions:
- Provide the main site for gas exchange.
- Take oxygen into the blood.
- Remove carbon dioxide from the blood.
- Participate in regulation of blood acid-base balance through carbon dioxide removal.
3. Explain the mechanism of breathing.
Answer:
Breathing, or pulmonary ventilation, is the movement of air into and out of the lungs. It consists mainly of inspiration and expiration.
Inspiration:
- The diaphragm contracts and moves downward.
- The external intercostal muscles contract.
- The volume of the thoracic cavity increases.
- Pressure inside the lungs decreases relative to atmospheric pressure.
- Air moves into the lungs.
Expiration:
- The diaphragm relaxes and moves upward.
- The thoracic cavity becomes smaller.
- Pressure inside the lungs increases relative to atmospheric pressure.
- Air moves out of the lungs.
During quiet breathing, expiration is mainly a passive process caused by the elastic recoil of the lungs and thoracic structures.
4. Describe the alveoli and explain the process of gaseous exchange.
Answer:
Alveoli are microscopic air sacs located at the ends of the respiratory passages. They are the principal sites of gas exchange between alveolar air and pulmonary capillary blood.
The alveolar walls are very thin and are closely surrounded by pulmonary capillaries. This provides a short pathway for diffusion of respiratory gases.
Oxygen exchange: Oxygen moves from the alveolar air into the pulmonary capillary blood.
Carbon dioxide exchange: Carbon dioxide moves from the pulmonary capillary blood into the alveoli and is removed during expiration.
Gas exchange occurs mainly by diffusion according to differences in the partial pressures of the gases.
5. Describe the respiratory tract from the nose to the alveoli.
Answer:
Air normally enters through the nose and passes through the nasal cavity. It then travels through the pharynx and larynx into the trachea.
The trachea divides into the right and left main bronchi. These enter the lungs and divide into smaller bronchi and bronchioles.
The bronchioles lead toward the respiratory portions of the lungs, ending in structures containing alveoli.
Sequence:
Nose → Nasal cavity → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli
6. Explain the transport of oxygen and carbon dioxide in the blood.
Answer:
Oxygen and carbon dioxide are transported between the lungs and body tissues through the blood.
Oxygen:
Most oxygen is transported bound to haemoglobin in red blood cells. A small amount is dissolved in plasma.
Carbon dioxide:
Carbon dioxide is transported in several forms. Most is carried as bicarbonate ions, while smaller amounts are transported bound to proteins such as haemoglobin or dissolved in plasma.
Short Answer Questions – 5 Marks
1. Write a short note on the nose and nasal cavity.
Answer: The nose and nasal cavity form an important entry passage for air. They filter, warm and humidify inspired air and also contain receptors involved in the sense of smell.
2. What is the pharynx?
Answer: The pharynx is a muscular passage behind the nose and mouth. It serves as a common passage for the respiratory and digestive systems and is divided into the nasopharynx, oropharynx and laryngopharynx.
3. Write a short note on the larynx.
Answer: The larynx is commonly called the voice box. It connects the pharynx with the trachea, contains the vocal cords and contributes to sound production. It also helps protect the lower airway during swallowing.
4. What is the trachea?
Answer: The trachea, or windpipe, is a tube that carries air from the larynx to the bronchi. Its cartilage rings help keep the airway open.
5. Differentiate between the right and left lung.
Answer:
| Right Lung | Left Lung |
|---|---|
| Has three lobes. | Has two lobes. |
| Generally wider and shorter. | Generally narrower because of the position of the heart. |
6. What is pleura?
Answer: Pleura is a serous membrane associated with the lungs. The visceral pleura covers the lungs, while the parietal pleura lines the thoracic cavity. Pleural fluid between the layers reduces friction during breathing.
7. What are alveoli?
Answer: Alveoli are microscopic air sacs in the lungs and are the main sites of gas exchange. Their thin walls are closely associated with pulmonary capillaries.
8. What is inspiration?
Answer: Inspiration is the movement of air into the lungs. During normal inspiration, the diaphragm contracts, thoracic volume increases and pressure inside the lungs falls below atmospheric pressure.
9. What is expiration?
Answer: Expiration is the movement of air out of the lungs. During quiet expiration, the diaphragm relaxes and the elastic recoil of the lungs helps move air outward.
10. What is the function of the diaphragm in respiration?
Answer: The diaphragm is the main muscle of quiet breathing. Its contraction increases thoracic volume and assists inspiration, while its relaxation contributes to expiration.
11. What is external respiration?
Answer: External respiration is the exchange of oxygen and carbon dioxide between the alveoli and pulmonary capillary blood.
12. What is internal respiration?
Answer: Internal respiration is the exchange of oxygen and carbon dioxide between systemic blood and body tissues.
Very Short Answer Questions
- What is respiration?
- Name the main organs of the respiratory system.
- How many lobes does the right lung have?
- How many lobes does the left lung have?
- What is the main muscle of quiet breathing?
- Where does gas exchange mainly occur?
- What is the voice box called?
- What is the windpipe called?
- What are alveoli?
- What is inspiration?
- What is expiration?
- What is pleura?
- Name the two main bronchi.
- How is most oxygen transported in blood?
- In what major form is most carbon dioxide transported?
Diagram-Based Questions
Students should practise drawing and labelling the following diagrams:
- Human respiratory system.
- Structure of the lungs showing lobes.
- Alveolus and surrounding pulmonary capillaries.
- Mechanism of inspiration and expiration.
- Respiratory tract from nose to alveoli.
Important Questions to Prepare First
If you have limited time before the examination, revise these questions first:
- Define the respiratory system and explain its functions.
- Describe the structure and functions of the lungs.
- Explain the mechanism of breathing.
- Describe the alveoli and explain gaseous exchange.
- Describe the respiratory tract from the nose to the alveoli.
- Explain the transport of oxygen and carbon dioxide.
- Write a short note on the diaphragm.
- Write a short note on pleura.
Exam Writing Tips
- Begin long answers with a clear definition.
- Use headings such as structure, functions and clinical importance where appropriate.
- Draw a labelled respiratory-system diagram when the question permits it.
- For questions on breathing, explain inspiration and expiration separately.
- For gas-exchange questions, mention alveoli, pulmonary capillaries and diffusion.
- For 5-mark questions, write focused points rather than unnecessary details.
- Use correct anatomical terminology and underline important terms in the examination.
Quick Revision
- Right lung: Three lobes.
- Left lung: Two lobes.
- Main muscle of quiet breathing: Diaphragm.
- Gas exchange: Mainly occurs in the alveoli.
- Inspiration: Air moves into the lungs.
- Expiration: Air moves out of the lungs.
- Oxygen: Mainly transported bound to haemoglobin.
- Carbon dioxide: Mainly transported as bicarbonate ions.
- External respiration: Gas exchange between alveoli and pulmonary blood.
- Internal respiration: Gas exchange between blood and tissues.
Related Study Resources
For a complete understanding of the chapter, read the Respiratory System theory notes for GNM 1st Year.
After revising these questions, practise the Respiratory System MCQs for GNM 1st Year.
Disclaimer: This material is provided for nursing education and examination preparation. It is not a substitute for professional medical advice, diagnosis or treatment.