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All questions of Respiration for Class 8 Exam
Which type of white blood cell is primarily responsible for fighting bacterial infections?- a)Lymphocytes
- b)Eosinophils
- c)Monocytes
- d)Neutrophils
Correct answer is option 'D'. Can you explain this answer?
Which type of white blood cell is primarily responsible for fighting bacterial infections?
a)
Lymphocytes
b)
Eosinophils
c)
Monocytes
d)
Neutrophils
 | Edgy Education answered |
Neutrophils are the most abundant white blood cells and are the first responders to bacterial infections, engulfing and digesting bacteria. Lymphocytes are involved in immune regulation, monocytes become macrophages, and eosinophils combat parasitic infections, making options A, C, and B incorrect for bacterial infections.
Which component of blood is responsible for carrying oxygen to the body’s tissues?- a)White blood cells
- b)Platelets
- c)Red blood cells
- d)Blood plasma
Correct answer is option 'C'. Can you explain this answer?
Which component of blood is responsible for carrying oxygen to the body’s tissues?
a)
White blood cells
b)
Platelets
c)
Red blood cells
d)
Blood plasma
 | Rahul Kumar answered |
Red blood cells contain hemoglobin, which binds oxygen in the lungs and transports it to tissues. They also carry carbon dioxide back to the lungs. White blood cells fight infections, platelets aid in clotting, and plasma transports nutrients and waste, making options A, B, and D incorrect for oxygen transport.
Which gas is essential for aerobic respiration to occur?- a)Nitrogen
- b)Carbon dioxide
- c)Oxygen
- d)Hydrogen
Correct answer is option 'C'. Can you explain this answer?
Which gas is essential for aerobic respiration to occur?
a)
Nitrogen
b)
Carbon dioxide
c)
Oxygen
d)
Hydrogen
 | Torcia Education answered |
Aerobic respiration requires oxygen to break down glucose, producing energy, carbon dioxide, and water. Oxygen is absorbed from inhaled air and transported to cells via the bloodstream. Nitrogen, carbon dioxide, and hydrogen are not required for this process, making options A, B, and D incorrect.
What is the primary source of energy for cellular respiration?- a)Proteins
- b)Vitamins
- c)Fats
- d)Carbohydrates
Correct answer is option 'D'. Can you explain this answer?
What is the primary source of energy for cellular respiration?
a)
Proteins
b)
Vitamins
c)
Fats
d)
Carbohydrates
 | Subset Academy answered |
Carbohydrates, broken down into glucose during digestion, are the primary source of energy for cellular respiration. Glucose is used in the mitochondria during aerobic respiration to produce energy. While fats and proteins can also provide energy, carbohydrates are the main source, and vitamins do not directly provide energy, making options A, C, and B incorrect.
What is the role of mitochondria in respiration?- a)To store glucose
- b)To release energy from glucose
- c)To produce carbon dioxide
- d)To transport oxygen
Correct answer is option 'B'. Can you explain this answer?
What is the role of mitochondria in respiration?
a)
To store glucose
b)
To release energy from glucose
c)
To produce carbon dioxide
d)
To transport oxygen
| | Edgy Education answered |
Mitochondria are the site of aerobic respiration, where glucose is broken down with oxygen to release energy in a controlled manner. While carbon dioxide is a by-product, the primary role is energy release. Mitochondria do not store glucose or transport oxygen, making options A, C, and D incorrect.
What is the primary purpose of respiration in living organisms?- a)To intake food
- b)To release energy from food
- c)To transport oxygen to the lungs
- d)To remove glucose from cells
Correct answer is option 'B'. Can you explain this answer?
What is the primary purpose of respiration in living organisms?
a)
To intake food
b)
To release energy from food
c)
To transport oxygen to the lungs
d)
To remove glucose from cells
| | Edgy Education answered |
Respiration is the process by which energy is released from food (glucose) within cells through chemical reactions. It occurs in every cell, not just the lungs, and is essential for providing energy for cellular functions. Options A, C, and D are incorrect as they do not accurately describe the primary purpose of respiration.
What happens to the chest cavity volume during exhalation?- a)It decreases
- b)It increases
- c)It remains unchanged
- d)It expands significantly
Correct answer is option 'A'. Can you explain this answer?
What happens to the chest cavity volume during exhalation?
a)
It decreases
b)
It increases
c)
It remains unchanged
d)
It expands significantly
| | Torcia Education answered |
During exhalation, the intercostal muscles and diaphragm relax, causing the ribs to drop and the diaphragm to return to its dome shape. This reduces the chest cavity volume, increasing pressure and pushing air out of the lungs. An increase or unchanged volume occurs during inhalation, making options B, C, and D incorrect.
What happens to the diaphragm during inhalation?- a)It contracts and moves downward
- b)It relaxes and moves upward
- c)It remains stationary
- d)It contracts and moves upward
Correct answer is option 'A'. Can you explain this answer?
What happens to the diaphragm during inhalation?
a)
It contracts and moves downward
b)
It relaxes and moves upward
c)
It remains stationary
d)
It contracts and moves upward
| | Subset Academy answered |
During inhalation, the diaphragm muscles contract, pulling the diaphragm downward. This increases the chest cavity volume, reducing pressure and drawing air into the lungs. Relaxation occurs during exhalation, and the diaphragm does not remain stationary or move upward during inhalation, making options B, C, and D incorrect.
What is the role of the trachea in the respiratory system?- a)To exchange gases with the bloodstream
- b)To connect the mouth and nose to the lungs
- c)To produce mucus for air filtration
- d)To store oxygen for respiration
Correct answer is option 'B'. Can you explain this answer?
What is the role of the trachea in the respiratory system?
a)
To exchange gases with the bloodstream
b)
To connect the mouth and nose to the lungs
c)
To produce mucus for air filtration
d)
To store oxygen for respiration
 | Tutorpedia Coaching answered |
The trachea (windpipe) serves as a passageway for air, connecting the mouth and nose to the lungs. It is supported by cartilage rings to remain open. Gas exchange occurs in the alveoli (not the trachea), mucus production is a secondary function, and the trachea does not store oxygen, making options A, C, and D incorrect.
Where does gas exchange primarily occur in the human respiratory system?- a)Trachea
- b)Bronchioles
- c)Alveoli
- d)Bronchi
Correct answer is option 'C'. Can you explain this answer?
Where does gas exchange primarily occur in the human respiratory system?
a)
Trachea
b)
Bronchioles
c)
Alveoli
d)
Bronchi
| | Tutorpedia Coaching answered |
Gas exchange, where oxygen enters the bloodstream and carbon dioxide is removed, occurs in the alveoli (air sacs). The thin walls of the alveoli and surrounding capillaries facilitate this diffusion. The trachea, bronchi, and bronchioles are primarily air passageways, not sites of gas exchange, making options A, B, and D incorrect.
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