Breathing and Exchange of Gases | MCQs | from 100% NCERT QUESTIONS | NEET(Que 32-47 of 100)

 

32. 

From NCERT

The CO2­ is trapped in the form of ___________ at the tissue level.

1. Bicarbonate

2. Carbonate

3. Both

4. CO2­

... Answer is 1)
View Explanation with NCERT Reference below all the questions.

33.

From NCERT

Which of the following helps in regulation the respiratory rhythm

1. Respiratory rhythm centre

2. Pneumotaxic centre

3. Aortic arch and carotid artery receptors

4. All of the above

... Answer is 4)
View Explanation with NCERT Reference below all the questions.

34.

From NCERT

The respiratory centre is highly sensitive for

1. CO2­

2. O2­

3. H+ ions

4. Both A and C

... Answer is 4)
View Explanation with NCERT Reference below all the questions.

35.

From NCERT

The respiratory centre is highly insensitive for

1. CO2­

2. O2­

3. H+ ions

4. Both 1 and 3

... Answer is 2)
View Explanation with NCERT Reference below all the questions.

36.

From NCERT

Aortic arch and carotid artery receptors cannot recognise changes in

1. CO2­ Concentration

2. O2­ Concentration

3. H+ ions Concentration

4. All of these

... Answer is 2)
View Explanation with NCERT Reference below all the questions.

37.

From NCERT

Pneumotaxic Centre is present in the

1. forebrain

2. midbrain

3. Hindbrain

4. Diencephalon

... Answer is 3)
View Explanation with NCERT Reference below all the questions.

38.

From NCERT

Respiratory rhythm Centre is present in the

1. forebrain

2. midbrain

3. Hindbrain

4. Diencephalon

... Answer is 3)
View Explanation with NCERT Reference below all the questions.

39.

From NCERT

Difficulty in breathing due to inflammation  of bronchi and bronchioles leads to

1. Asthma

2. Emphysema

3. Occupational Lung Disease

4. Rhinitis

... Answer is 1)
View Explanation with NCERT Reference below all the questions.

40.

From NCERT

Which of the following disease is caused mainly due to cigarette smoking

1. Asthma

2. Emphysema

3. Bronchitis

4. Rhinitis

... Answer is 2)
View Explanation with NCERT Reference below all the questions.

41.

From NCERT

______ temperature will shift the Oxyhaemoglobin dissociation Curve to _____side,

1. lower, left

2. higher, right

3. lower, right

4. Both A and B

... Answer is 4)
View Explanation with NCERT Reference below all the questions.

42.

From NCERT

Which of the following factors are favourable for the shifting of Oxyhaemoglobin dissociation Curve to the left side

1. High pO2

2. Low pCO2

3. less H+ Concentration

4. All of these

... Answer is 4)
View Explanation with NCERT Reference below all the questions.

43.

From NCERT

A curve obtained when percentage saturation of Hb with O2 is plotted against the pO2 is also called as

1. Association curve

2. Dissociation Curve

3. Sigmoid Curve

4. Both 2 and 3

... Answer is 4)
View Explanation with NCERT Reference below all the questions.

44.

From NCERT

Which of the following is true for transport of gases

1. Maximum amount of O2 is transported by RBCs

2. Maximum amount of CO2 is transported by Plasma as Bicarbonates

3. Plasma transports both CO2 and O2

4. All of the above

... Answer is 4)
View Explanation with NCERT Reference below all the questions.

45. 

From NCERT

What percentage of Carbon dioxide is transported in a dissolved state through plasma

1. 7

2. 20-25

3. 70

4. 97

... Answer is 1)
View Explanation with NCERT Reference below all the questions.

46. 

From NCERT

What percentage of Carbon dioxide is transported by RBCs

1. 7

2. 20-25

3. 70

4. 97

... Answer is 2)
View Explanation with NCERT Reference below all the questions.

16. 

... Answer is B)
View Explanation with NCERT Reference below all the questions.

Section showing-View Explanation with NCERT Reference below all the questions. 

33- 

 'Respiratory Rhythm Center'

• A special centre in the medulla region of the brain is primarily responsible for regulating respiratory rhythms.
• 

34-
A specialised centre present in the medulla region of the brain called respiratory rhythm centre is primarily responsible for this regulation. A chemosensitive area is situated adjacent to the rhythm centre which is highly sensitive to CO2 and hydrogen ions.

All Cocepts used here in one shot-

• Blood is the medium of transport for oxygen and carbon dioxide. About 97% of oxygen is transported by RBCs in the blood. The remaining 3% of oxygen is carried in a dissolved state through the plasma. Nearly 20-25% of carbon dioxide is transported by RBCs whereas 70% of it is carried as bicarbonate ions. About 7% of carbon dioxide is carried in a dissolved state through plasma. 10% of the carbon dioxide is carried in form of carbonic acid.

Hypoxia Vs Hypoxemia 

• If a tissue is having inadequate supply of oxygen, the condition is called as hypoxia. Hypoxia differs from hypoxemia in that hypoxia is a state in which oxygen supply is insufficient, whereas hypoxemia refers specifically to the state where there is low arterial oxygen supply. Hypoxia in which there is complete deprivation of oxygen supply is referred to as "anoxia". Check out the given illustration to clear the confusion and then attempt the question given below.

Concepts
10 min read

Breathing And Exchange Of Gases
- A quick revision tool for the grip on the chapter.
1
Human respiratory system

1. Human respiratory system helps to inhale the respiratory gas which is distributed by all through the body and the carbon dioxide is exhaled.
2. The nasal cavity, larynx, trachea, alveoli and lungs are the part of human respiratory system.
2
Difference between inspiration and expiration

Part of the respiratory system	Inspiration	Expiration
Diaphragm	Contracts and flattens downwards	Relaxes and moves upwards
External intercostal muscles   Internal intercostal muscles	Muscles contract Relaxed	Muscles relax   Contracts
Rib cage and sternum	Move upwards and outwards	Move downwards and inwards
Thoracic cavity	Increases	Decreases
Air pressure	Decrease inside thorax and lungs	Increase inside thorax and lungs
Air movement	Extreme air pressure drives air into lungs at low pressure	Air forced out of lungs by thorax compression and elastic recoil of lungs

3

Capacities of the lungs

1. Tidal volume- The amount of air breathed in and out in normal quiet breathing. It is about 500 ml.
2. Dead air space- Some of the air in the trachea and bronchi do not take part in breathing, called dead air space. it is about 150ml.
3. Alveolar air- The tidal volume contained in alveoli. It is about 350ml.
4. Inspiratory reserve volume- The inspiratory reserve volume (IRV), about 3,000 mL. It is the additional air that can be forcibly inhaled after the inspiration of a normal tidal volume.
5. Expiratory reserve volume- The expiratory reserve volume (ERV)is the additional air that can be forcibly exhaled after the expiration of a normal tidal volume. It is about 1,200 mL.
6. Vital capacity- The maximum amount of air a person can expel from the lungs after a maximum inhalation. It is about 4500 ml.
7. Residual volume- The volume of air that remains in the lungs even after maximum or forceful expiration. The average Residual Volume (RV) in healthy males is about 1200 ml. In females, the average RV is 1100 ml.
8. Total lung capacity- Maximum amount of air that can be held at any time in the two lungs, called total lung capacity. It is about 6000 ml.

4

Functional residual capacity

1. Lung capacities are nothing but the sum of two or more lung volumes.
2. There are four major lung capacities that can be calculated from the summation of two or more lung volumes
3. Functional residual capacity equals the sum of expiratory reserve volume (ERV) and the residual volume (RV)
4. In other words, functional residual capacity is the amount of air that remains in the lungs of an individual at the end of normal expiration.
5. It is represented by the formula FRC= ERV + RV
6. The average FRC values in males is 2400 ml [ERV(1200 ml) + RV (1200 ml)] and in females it is 1800 ml [ERV (700 ml) + RV (1100 ml)]

5

Residual volume

1. The volume of air that remains in the lungs even after maximum or forceful expiration.
2. Residual volume is the only lung volume that cannot be measured directly using a spirometer.
3. The residual volume exists because the pleural fluid stretches and holds the lungs against the ribs.
4. The average Residual Volume (RV) in healthy males is about 1200 ml.
5. In females, the average RV is 1100 ml.
6. RV may be significantly high in obstructive lung diseases.

6

Transport of oxygen in the blood

Oxygen is transported in the following manner:
1. As dissolved gas
2. As oxyhaemoglobin

7

Transport of carbon dioxide

It is transported in three ways:
1. Transport of CO2​ in dissolved form
2. Transport of CO2​ as a bicarbonate
3. Transport of CO2​ as carbaminohaemoglobin

8

Factors affecting oxygen hemoglobin dissociation curve

Factors affecting the oxygen hemoglobin dissociation curve are as follows:
1. Shift to right: It indicates dissociation of oxygen from haemoglobin.
2. Shift to left: It indicates acceptance of oxygen by haemoglobin.

9

Pons respiratory centres

Pneumotaxic centre
1. It is located in the dorsal part of pons varolii.
2. Its function is to limit inspiration.
Apneustic centre
1. It is located in the lower part of pons varolii.
2. It controls the depth of inspiration.

10

Occupational respiratory disorders

Cause:
1. Exposure to silicosis and asbestoses
Symptoms:
1. Inflammation