100%

Total Marks: 50

Time: 60 min

Questions: 25

Biology (SNC) – 1st Year

Chapter: #10 – Human Respiratory System

Subject: Biology

Level: 1st Year Science

Type: Practice Quiz

🫁

💨

Chapter 10: Human Respiratory System

Multiple Choice Questions (10×1=10)

During inhalation, diaphragm:

A Contracts and moves upward

B Contracts and moves downward

C Relaxes and moves upward

D Relaxes and moves downward

Our cells obtain oxygen from ……:

A Lungs

B Blood

C Air

D Throat

What is the primary function of the lower respiratory tract?

A To produce sound

B To conduct air to the lungs and facilitate gas exchange

C To filter and warm incoming air

D To secrete digestive enzymes

Which part of the brain controls the breathing rhythm?

A Cerebellum

B Medulla oblongata

C Hypothalamus

D Cerebrum

How many polypeptide chains are present in myoglobin?

A 1

B 2

C 4

D 8

Which of the following is NOT a function of respiratory pigments?

A Oxygen transport

B Oxygen storage

C Carbon dioxide transport

D Protein synthesis

Pneumonia can be prevented by ……:

A Vaccination

B Antibiotics only

C Surgery

D No prevention possible

COPD is ……:

A Acute bacterial infection

B Chronic inflammatory disease

C Autoimmune disorder

D Viral infection

Chronic bronchitis is a type of ……:

A Asthma

B COPD

C Lung cancer

D Tuberculosis

How long can chronic bronchitis last?

A 1 week

B 3 months to 2 years

C 5 years

D A lifetime

Short Answer Questions (15×2=30)

[1]
What are the advantages of having millions of alveoli rather than a pair of simple balloon-like lungs?
[ii]
Differentiate between:
- Internal and external respiration
- Upper and lower respiratory tract
- Bronchi and bronchioles
- Haemoglobin and myoglobin
[iii]
List three properties of an effective respiratory surface.
[iv]
Name the organs of the upper respiratory tract.
[v]
How does the epiglottis function during swallowing?
[vi]
What is the glottis?
[vii]
How does air reach the alveoli?
[viii]
How is carbon dioxide removed from the blood?
[ix]
What is the pleural cavity?
[x]
How does the medulla oblongata control breathing?
[xi]
Why is breathing more difficult at high altitudes?
[xii]
What is the role of the iron in the haem group of haemoglobin?
[xiii]
What are the four locations of sinuses in the skull?
[xiv]
What serious complications can occur in advanced pulmonary tuberculosis?
[xv]
What is alpha-1 antitrypsin deficiency, and how does it relate to COPD?

Detailed Answer Questions (Answer any 2) (2×5=10)

1. Explain the process of breathing (ventilation) in humans including the roles of the diaphragm, intercostal muscles, and pleural membranes. How does the body regulate this process?

Breathing Mechanism:

Inhalation (Inspiration):
• Diaphragm contracts and flattens
• External intercostal muscles contract
• Rib cage moves upward and outward
• Thoracic volume increases
• Lung pressure decreases
• Air rushes in

Exhalation (Expiration):
• Diaphragm relaxes and domes upward
• External intercostal muscles relax
• Rib cage moves downward and inward
• Thoracic volume decreases
• Lung pressure increases
• Air is pushed out

2. Why does myoglobin have a higher oxygen-binding affinity than haemoglobin? Discuss its physiological importance?

Characteristic	Hemoglobin	Myoglobin
Structure	4 polypeptide chains (2α + 2β), 4 heme groups	1 polypeptide chain, 1 heme group
Oxygen Binding	Cooperative (S-shaped curve)	Non-cooperative (hyperbolic curve)
Affinity for O₂	Lower (P₅₀ ≈ 26 mmHg)	Higher (P₅₀ ≈ 2-3 mmHg)
Location	Red blood cells (circulation)	Muscle cells (storage)
Function	O₂ transport from lungs to tissues	O₂ storage in muscles for immediate use

3. What is COPD and how it can be treated? Analyze the impact of genetic and environmental factors on the development of COPD.

COPD Overview:

COPD (Chronic Obstructive Pulmonary Disease):
• Progressive lung disease causing airflow obstruction
• Two main forms: Chronic bronchitis & Emphysema
• Symptoms: Chronic cough, sputum production, dyspnea
• Risk factors: Smoking (primary), pollution, occupational exposure

Treatment Approaches:
• Smoking cessation (most important)
• Bronchodilators (inhalers)
• Corticosteroids (reduce inflammation)
• Oxygen therapy (advanced cases)
• Pulmonary rehabilitation
• Surgery (severe cases)

Human Respiratory System Quiz

Biology (SNC) – 1st Year

Chapter 10: Human Respiratory System

Multiple Choice Questions (10×1=10)

Short Answer Questions (15×2=30)

Detailed Answer Questions (Answer any 2) (2×5=10)