1. What is the primary function of the human respiratory system?
A) Digestion
B) Circulation
C) Gas exchange
D) Excretion
Answer: C) Gas exchange
2. Which organ is mainly responsible for breathing?
A) Heart
B) Lungs
C) Liver
D) Kidneys
Answer: B) Lungs
3. The windpipe is also known as:
A) Esophagus
B) Bronchus
C) Trachea
D) Larynx
Answer: C) Trachea
4. Tiny air sacs in the lungs are called:
A) Bronchi
B) Alveoli
C) Nephrons
D) Capillaries
Answer: B) Alveoli
5. Oxygen is transported in the blood by:
A) Platelets
B) Plasma
C) Hemoglobin
D) White blood cells
Answer: C) Hemoglobin
6. The process of inhaling air is called:
A) Expiration
B) Inspiration
C) Ventilation
D) Diffusion
Answer: B) Inspiration
7. The diaphragm is a:
A) Bone
B) Nerve
C) Muscle
D) Gland
Answer: C) Muscle
8. Carbon dioxide is removed from the body during:
A) Inhalation
B) Digestion
C) Exhalation
D) Circulation
Answer: C) Exhalation
9. The voice box is also called:
A) Pharynx
B) Trachea
C) Larynx
D) Bronchiole
Answer: C) Larynx
10. The exchange of gases in the lungs occurs in the:
A) Bronchi
B) Alveoli
C) Trachea
D) Larynx
Answer: B) Alveoli
11. The right lung has how many lobes?
A) 1
B) 2
C) 3
D) 4
Answer: C) 3
12. The left lung has how many lobes?
A) 1
B) 2
C) 3
D) 4
Answer: B) 2
13. The nasal cavity primarily functions to:
A) Pump blood
B) Filter and warm air
C) Digest food
D) Produce hormones
Answer: B) Filter and warm air
14. The bronchi branch into smaller tubes called:
A) Alveoli
B) Bronchioles
C) Capillaries
D) Arteries
Answer: B) Bronchioles
15. The process of breathing in and out is called:
A) Circulation
B) Respiration
C) Ventilation
D) Digestion
Answer: C) Ventilation
16. Cellular respiration occurs in the:
A) Lungs
B) Heart
C) Mitochondria
D) Kidneys
Answer: C) Mitochondria
17. The epiglottis prevents food from entering the:
A) Esophagus
B) Stomach
C) Trachea
D) Liver
Answer: C) Trachea
18. Breathing rate increases during exercise because:
A) Oxygen demand increases
B) Blood pressure decreases
C) Temperature decreases
D) Heart stops
Answer: A) Oxygen demand increases
19. The pleura is a:
A) Muscle
B) Membrane covering lungs
C) Air sac
D) Blood vessel
Answer: B) Membrane covering lungs
20. Which gas makes up most of the air we breathe?
A) Oxygen
B) Carbon dioxide
C) Nitrogen
D) Hydrogen
Answer: C) Nitrogen
21. The respiratory center that controls breathing is located in the:
A) Cerebrum
B) Medulla oblongata
C) Spinal cord
D) Cerebellum
Answer: B) Medulla oblongata
22. Which structure connects the throat to the trachea?
A) Bronchi
B) Pharynx
C) Alveoli
D) Diaphragm
Answer: B) Pharynx
23. Smoking primarily damages the:
A) Heart valves
B) Liver cells
C) Alveoli
D) Kidneys
Answer: C) Alveoli
24. The movement of gases across the alveolar membrane occurs by:
A) Active transport
B) Diffusion
C) Osmosis
D) Filtration
Answer: B) Diffusion
25. Asthma mainly affects the:
A) Bronchioles
B) Alveoli
C) Diaphragm
D) Nasal cavity
Answer: A) Bronchioles
26. During inhalation, the diaphragm moves:
A) Upward
B) Downward
C) Sideways
D) Forward
Answer: B) Downward
27. The exchange of oxygen and carbon dioxide between blood and tissues is called:
A) External respiration
B) Internal respiration
C) Ventilation
D) Inspiration
Answer: B) Internal respiration
28. The smallest branches of the bronchi are called:
A) Alveoli
B) Bronchioles
C) Capillaries
D) Lobes
Answer: B) Bronchioles
29. A person with low hemoglobin will have difficulty in:
A) Digesting food
B) Pumping blood
C) Carrying oxygen
D) Producing hormones
Answer: C) Carrying oxygen
30. Which muscle helps in forced exhalation?
A) Biceps
B) Abdominal muscles
C) Triceps
D) Deltoid
Answer: B) Abdominal muscles