Practice Corner MCQs

Question 1 of 104

1. Question

Read the given statements and select the correct option.
Statement 1: Respiration is most efficient in the insects, among the invertebrates.
Statement 2: In the insects, air is carried directly to the cells by tracheoles.

Both statements 1 and 2 are correct.
Statement 1 is correct but statement 2 is incorrect.
Statement 1 is incorrect but statement 2 is correct.
Both statements 1 and 2 are incorrect.

Question 2 of 104

2. Question

Read the given statements characterising certain types of animals. Select the option which correctly exemplifies each of these types.
(i) Animal having external gills
(ii) Animal having internal gills
(iii) Animal showing tracheal respiration
(iv) Animal revealing buccopharyngeal respiration

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } & \text { (iv) } \\
\hline \text { (a) } & \text { Prawn } & \text { Arenicola } & \text { Unio } & \text { Fish } \\
\hline \text { (b) } & \text { Necturus } & \text { Unio } & \text { Prawn } & \text { Frog } \\
\hline \text { (c) } & \text { Pila } & \text { Arenicola } & \text { Unio } & \text { Toad } \\
\hline \text { (d) } & \text { Necturus } & \text { Pila } & \text { Millipede } & \text { Toad } \\
\hline
\end{array}
\)

a
b
c
d

Question 3 of 104

3. Question

Match column I with column II and select the correct option from the given codes.

\(
\begin{array}{|c|l|c|l|}
\hline & \begin{array}{l}
\text { Column I } \\
\text { (Animals) }
\end{array} & & \begin{array}{l}
\text { Column II } \\
\text { (Respiratory structures) }
\end{array} \\
\hline \text { A. } & \text { Pigeon } & \text { (i) } & \text { Book gills } \\
\hline \text { B. } & \text { Scorpion } & \text { (ii) } & \text { Pharyngeal wall } \\
\hline \text { C. } & \text { Planaria } & \text { (iii) } & \text { Lungs } \\
\hline \text { D. } & \text { Earthworm } & \text { (iv) } & \text { Gills } \\
\hline \text { E. } & \text { Spiders } & \text { (v) } & \text { Book lungs } \\
\hline \text { F. } & \text { King crab } & \text { (vi) } & \text { Body surface } \\
\hline \text { G. } & \text { Prawn } & \text { (vii) } & \text { Moist cuticle } \\
\hline \text { H. } & \text { Labeo } & & \\
\hline
\end{array}
\)

A-(iii), B-(v), C-(vi), D-(vii), E-(v), F-(i), G-(iv), H-(iv)
A-(v), B-(ii), C-(vi), D-(vii), E-(vi), F-(iv), G-(i), H-(iii)
A-(vi), B-(iv), C-(vii), D-(v), E-(i), F-(ii), G-(iii), H-(vii)
A-(i), B-(v), C-(vii), D-(iii), E-(vii), F-(ii), G-(iv), H-(vi)

Question 4 of 104

4. Question

Which structure of man is similar to spiracle of cockroach?

Nostril
Bronchiole
Lung
Alveolus

Question 5 of 104

5. Question

Which of the following options is incorrect about the larynx (sound box)?

It is a bony box.
Glottis is the opening into the larynx.
During swallowing of food glottis is covered by epiglottis to prevent food entry into the larynx.
All of these

Question 6 of 104

6. Question

Which of the following structures close the glottis during swallowing to prevent the entry of food into windpipe?

Tongue
Epiglottis
Diaphragm
Larynx

Question 7 of 104

7. Question

In man and mammals, air passes from outside into the lungs through

nasal cavity, larynx, pharynx, trachea, bronchi, alveoli
nasal cavity, pharynx, larynx, trachea, bronchioles, bronchi, alveoli
nasal cavity, larynx, pharynx, trachea, bronchioles, alveoli
nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, alveoli.

Question 8 of 104

8. Question

Study the given figure of respiratory passage carefully and identify the parts labelled as A, B, C, D and E.

\(
\begin{array}{|c|c|c|c|c|c|}
\hline & \text { A } & \text { B } & \text { C } & \text { D } & \mathbf{E} \\
\hline \text { (a) } & \text { Alveolar } & \begin{array}{l}
\text { Secondary } \\
\text { bronchus }
\end{array} & \text { Alveoli } & \text { Bronchioles } & \text { Trachea } \\
\hline \text { (b) } & \text { Alveoli } & \begin{array}{l}
\text { Secondary } \\
\text { bronchus }
\end{array} & \begin{array}{l}
\text { Alveolar } \\
\text { sac }
\end{array} & \text { Trachea } & \text { Bronchioles } \\
\hline \text { (c) } & \begin{array}{l}
\text { Alveolar } \\
\text { sac }
\end{array} & \begin{array}{l}
\text { Tertiary } \\
\text { bronchus }
\end{array} & \text { Alveoli } & \text { Trachea } & \text { Bronchioles } \\
\hline \text { (d) } & \text { Alveoli } & \begin{array}{l}
\text { Tertiary } \\
\text { bronchus }
\end{array} & \begin{array}{l}
\text { Alveolar } \\
\text { sac }
\end{array} & \text { Bronchioles } & \text { Trachea } \\
\hline
\end{array}
\)

a
b
c
d

Question 9 of 104

9. Question

Mammalian lungs have an enormous number of minute alveoli (air sacs). This is to allow

more surface area for diffusion of gases
more space for increasing the volume of inspired air
more nerve supply to keep the lungs working
more spongy texture for keeping lung in proper shape

Question 10 of 104

10. Question

The given figure shows the diagrammatic view of human respiratory system. Identify A, B, C and D.

A-Epiglottis, B-Alveoli, C-Bronchus, D-Diaphragm
A-Epiglottis, B-Alveoli, C-Bronchioles, D-Diaphragm
A-Sound box, B-Alveoli, C-Bronchus, D-Diaphragm
A-Larynx, B-Alveoli, C-Bronchioles, D-Diaphragm

Question 11 of 104

11. Question

The given figures are of human larynx, front view (i) and vertical section (ii).

Identify the labelled parts A to D.

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { A } & \text { B } & \text { C } & \text { D } \\
\hline \text { (a) } & \text { Glottis } & \text { Larynx } & \text { Vocal cord } & \begin{array}{l}
\text { Cartilaginous rings } \\
\text { of trachea }
\end{array} \\
\hline \text { (b) } & \text { Epiglottis } & \begin{array}{l}
\text { Cartilaginous rings } \\
\text { of trachea }
\end{array} & \text { Trachea } & \text { Thyroid cartilage } \\
\hline \text { (c) } & \text { Glottis } & \begin{array}{l}
\text { Cartilaginous rings } \\
\text { of trachea }
\end{array} & \text { Larynx } & \text { Trachea } \\
\hline \text { (d) } & \text { Epiglottis } & \begin{array}{l}
\text { Bony rings of } \\
\text { trachea }
\end{array} & \begin{array}{l}
\text { Thyroid } \\
\text { cartilage }
\end{array} & \text { Trachea } \\
\hline
\end{array}
\)

a
b
c
d

Question 12 of 104

12. Question

Lungs are enclosed in

perichondrium
pericardium
pleural membrane
peritoneum

Question 13 of 104

13. Question

Thoracic chamber is formed dorsally by the (i). ventrally by the (iii), laterally by the (iii) and on lower side by the dome shaped (iv).
Select the correct option to complete the above paragraph.

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } & \text { (iv) } \\
\hline \text { (a) } & \begin{array}{l}
\text { vertebral } \\
\text { column }
\end{array} & \text { sternum } & \text { ribs } & \text { diaphragm } \\
\hline \text { (b) } & \text { sternum } & \begin{array}{l}
\text { vertebral } \\
\text { column }
\end{array} & \text { diaphragm } & \text { ribs } \\
\hline \text { (c) } & \text { diaphragm } & \text { ribs } & \text { vertebral column } & \text { sternum } \\
\hline \text { (d) } & \text { ribs } & \text { diaphragm } & \begin{array}{l}
\text { vertebral } \\
\text { column }
\end{array} & \text { sternum } \\
\hline
\end{array}
\)

a
b
c
d

Question 14 of 104

14. Question

Given below is a list of different steps (i-vi) involved in respiration.
(i) Utilisation of \(\mathrm{O}_2\) by the cells for catabolic reactions.
(ii) Transport of gases by the blood.
(iii) Pulmonary ventilation by which atmospheric air is drawn in and \(\mathrm{CO}_2\) is released out.
(iv) Release of resultant \(\mathrm{CO}_2\).
(v) Diffusion of \(\mathrm{O}_2\) and \(\mathrm{CO}_2\) between blood and tissues.
(vi) Diffusion of gases \(\left(\mathrm{O}_2\right.\) and \(\left.\mathrm{CO}_2\right)\) across alveolar tissues.
Select an option which has correct sequence of all the steps.

(iii), (vi), (ii), (v), (i), (iv)
(iii), (vi), (i), (v), (ii), (iv)
(iv), (ii), (v), (iii), (i), (vi)
(iv), (vi), (ii), (v), (i), (iii)

Question 15 of 104

15. Question

Inspiration occurs when there is a negative pressure in the lungs with respect to atmospheric pressure. This negative pressure is achieved when

intrapulmonary pressure is less than the atmospheric pressure
intrapulmonary pressure is greater than the atmospheric pressure
intrapulmonary pressure is equal to the atmospheric pressure
intrapleural pressure becomes more than the intraalveolar pressure

Question 16 of 104

16. Question

Read the given statements and select the correct option.
Statement 1: Mammals can eat while breathing.
Statement 2: Mammals have negative pressure breathing.

Both statements 1 and 2 are correct.
Statement 1 is correct but statement 2 is incorrect.
Statement 1 is incorrect but statement 2 is correct.
Both statements 1 and 2 are incorrect.

Question 17 of 104

17. Question

Which of the following parts are involved in the mechanism of breathing?

Abdominal muscles
Intercostal muscles
Diaphragm
All of these

Question 18 of 104

18. Question

Fill up the blanks in the following paragraph by selecting the correct option.
The movement of air into and out of the lungs is carried out by creating a (i) between the lungs and the atmosphere. Inspiration can occur if intra-pulmonary pressure is (ii) than the atmospheric pressure. Expiration takes place when the intra-pulmonary pressure is (iii) than the atmospheric pressure. Inspiration is initiated by the (iv) of diaphragm which (v) the volume of thoracic chamber in the antero-posterior axis.

\(
\begin{array}{|l|l|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } & \text { (iv) } & \text { (v) } \\
\hline \text { (a) } & \begin{array}{l}
\text { concentration } \\
\text { gradient }
\end{array} & \text { less } & \text { higher } & \text { relaxation } & \text { increases } \\
\hline \text { (b) } & \begin{array}{l}
\text { concentration } \\
\text { gradient }
\end{array} & \text { higher } & \text { less } & \text { contraction } & \text { decreases } \\
\hline \text { (c) } & \text { pressure gradient } & \text { higher } & \text { less } & \text { relaxation } & \text { decreases } \\
\hline \text { (d) } & \text { pressure gradient } & \text { less } & \text { higher } & \text { contraction } & \text { increases } \\
\hline
\end{array}
\)

a
b
c
d

Question 19 of 104

19. Question

Which of the following sequences is correct to initiate inspiration?
(i) The contraction of external intercostal muscles raises the ribs and sternum
(ii) Volume of thorax increases in the dorso-ventral axis
(iii) Intrapulmonary pressure decreases
(iv) Diaphragm contraction
(v) Air rushes into lungs
(vi) Volume of thorax increases in the anterior-posterior axis

(i), (ii), (iv), (v), (iii), (vi)
(i), (ii), (iv), (vi), (iii), (v)
(i), (ii), (iii), (iv), (vi), (v)
(vi), (v), (i), (ii), (iii), (iv)

Question 20 of 104

20. Question

Which of the following changes occur in diaphragm and intercostal muscles when expiration of air takes place?

Internal intercostal muscles relax and diaphragm contracts
External intercostal muscles and diaphragm relax
Internal intercostal muscles contract and diaphragm relax
External intercostal muscles and diaphragm contract

Question 21 of 104

21. Question

During expiration, the diaphragm becomes

dome-shaped
concave
oblique
flattened

Question 22 of 104

22. Question

Exhalation is the process of expulsion of air through the respiratory tract. Which figure illustrates the process of exhalation?

a
b
c
d

Question 23 of 104

23. Question

The given figure illustrates the changes in lung volume during the process of breathing.

The change from II to III indicates the

movement of diaphragm away from the lungs
expansion of the thoracic cavity
movement of air out of the lungs
expansion of ribs

Question 24 of 104

24. Question

Which of the following statements about the mechanism of ventilation/breathing is incorrect?

As the diaphragm relaxes, air is expelled from the respiratory system.
During inspiration the lungs act as suction pump.
Inspiration is a passive and expiration is an active process.
For quiet breathing, external intercostal muscles and diaphragm play an important role.

Question 25 of 104

25. Question

Select the correct statement.

Expiration takes place when intra-pulmonary pressure is higher than atmospheric pressure.
Contraction of external intercostal muscles decrease the volume of thoracic chamber.
Increase in pulmonary volume increases intrapulmonary pressure.
All of these

Question 26 of 104

26. Question

A person breathing normally at rest, takes in and expels approximately half a litre of air during each respiratory cycle. This is called

inspiratory reserve volume
tidal volume
expiratory reserve volume
vital capacity

Question 27 of 104

27. Question

Which one of the following statements is incorrect?

The principal of countercurrent flow facilitates efficient respiration in gills of fishes.
The residual air in lungs slightly decreases the efficiency of respiration in mammals.
The presence of non-respiratory air sacs, increases the efficiency of respiration in birds.
In insects, circulating body fluids serve to distribute oxygen to tissues.

Question 28 of 104

28. Question

Given below are four respiratory capacities and their respiratory volumes.

\(
\begin{array}{|c|l|c|}
\hline & \begin{array}{c}
\text { Respiratory volumes and } \\
\text { capacities }
\end{array} & \text { Volume of air } \\
\hline \text { (i) } & \text { Tidal volume } & 500 \mathrm{~mL} \\
\hline \text { (ii) } & \text { Vital capacity } & 2500 \mathrm{~mL} \\
\hline \text { (iii) } & \text { Functional residual capacity } & 2300 \mathrm{~mL} \\
\hline \text { (iv) } & \text { Total lung capacity } & 3200 \mathrm{~mL} \\
\hline
\end{array}
\)

Select the correct matched pair.

(i) and (ii)
(ii) and (iii)
(i) and (iii)
(iii) and (iv)

Question 29 of 104

29. Question

Complete the following sentences by selecting the correct option.
(A) Inspiratory capacity (IC) = (i) + IRV
(B) (ii) \(=T V+I R V+E R V\)
(C) Functional residual capacity (FRC) \(=E R V+\) (iii)

\(
\begin{array}{|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } \\
\hline \text { (a) } & \text { Vital capacity } & \text { Tidal volume } & \text { Residual volume } \\
\hline \text { (b) } & \text { Expiratory capacity } & \text { Residual volume } & \begin{array}{l}
\text { Inspiratory reserve } \\
\text { volume }
\end{array} \\
\hline \text { (c) } & \text { Tidal volume } & \text { Vital capacity } & \text { Residual volume } \\
\hline \text { (d) } & \text { Tidal volume } & \text { Total lung capacity } & \text { Expiratory capacity } \\
\hline
\end{array}
\)

a
b
c
d

Question 30 of 104

30. Question

Consider the following statements each with one or two blanks.

(i) Left lung has (1) lobes and right lung has (2) lobes.
(ii) Prawn respires with (3) and insects with (4).
(iii) Amount of air inhaled and exhaled with maximum effort is referred to as the (5) of the lungs. Fill up the above blanks by selecting the correct option.

Fill up the above blanks by selecting the correct option.

(1) – three, (2) – two, (3) – gills (4)-tracheae
(1) – two, (2) – three, (5) – vital capacity
(3) – gills, (4) – tracheae, (5) – tidal volume
(3) – tracheae, (4) – gills, (5) – tidal volume

Question 31 of 104

31. Question

Consider the following statements each with two blanks.
(i) Actually, only about (1) \(\mathrm{mL}\) of air enters the lung alveoli for the exchange of gases. The remaining fills the respiratory passage and is termed (2).
(ii) The amount of air which one can inhalewith maximum effort and also exhale with maximum effort is termed as (3). It is about (4) in normal adult person.
(iii) During normal quiet breathing, on an average, approximately (5) \(\mathrm{mL}\) of air is inspired or expired by adult human male in each breath. It is termed as (6) volume.
Which of the following options gives the correct fill-ups for the respective blank numbers from (1) to (6) in the above statements?

(3)-vital capacity, (4)-4000 mL, (5)-500, (6)-tidal
(1)-100, (2)-residual volume, (3)-functional residual capacity, (4)-3000 mL
(1)-350, (2)-dead space air, (5)-1000, (6)-inspiratory reserve
(1)-350, (2)-residual volume, (3)-vital capacity, (4) \(-4000 \mathrm{~mL}\)

Question 32 of 104

32. Question

The inspiratory capacity includes

tidal volume + expiratory reserve volume
tidal volume + inspiratory reserve volume
inspiratory reserve volume + expiratory reserve volume
expiratory reserve volume + residual volume

Question 33 of 104

33. Question

Vital capacity of lungs is

IRV + ERV
IRV + ERV + TV + RV
IRV+ERV+TV-RV
IRV + ERV + TV

Question 34 of 104

34. Question

After forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to

Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV) + Tidal Volume (TV) + Residual Volume (RV)
\(I R V+R V+E R V\)
\(I R V+T V+E R V\)
\(T V+R V+E R V\)

Question 35 of 104

35. Question

Match column I with column II and select the correct option from the given codes.
\(
\begin{array}{|l|l|l|l|}
\hline & \text { Column I } & & \text { Column II } \\
\hline \text { A. } & \text { Tidal volume } & \text { (i) } & 2500-3000 \mathrm{~mL} \text { of air } \\
\hline \text { B. } & \text { Inspiratory reserve volume } & \text { (ii) } & 1000 \mathrm{~mL} \text { of air } \\
\hline \text { C. } & \text { Expiratory reserve volume } & \text { (iii) } & 500 \mathrm{~mL} \text { of air } \\
\hline \text { D. } & \text { Residual volume } & \text { (iv) } & 3400-4800 \mathrm{~mL} \text { of air } \\
\hline \text { E. } & \text { Vital capacity } & \text { (v) } & 1200 \mathrm{~mL} \text { of air } \\
\hline
\end{array}
\)

A-(iii), B-(iv), C-(ii), D-(i), E-(v)
A-(iii), B-(i), C-(ii), D-(v), E-(iv)
A-(iii), B-(i), C-(iv), D-(v), E-(ii)
A-(v), B-(i), C-(ii), D-(iii), E-(iv)

Question 36 of 104

36. Question

Match column I with column II and select the correct option from the codes given below.
\(
\begin{array}{|l|l|l|l|}
\hline & \text { Column I } & & \text { Column II } \\
\hline \text { A. } & \text { TV + ERV } & \text { (i) } & \text { Expiratory capacity } \\
\hline \text { B. } & \text { RV + ERV + TV + IRV } & \text { (ii) } & \text { Total lung capacity } \\
\hline \text { C. } & \text { ERV + RV } & \text { (iii) } & \begin{array}{l}
\text { Functional residual } \\
\text { capacity }
\end{array} \\
\hline
\end{array}
\)

A-(i), B-(ii), C-(iii)
A-(iii), B-(i), C-(ii)
A-(iii), B-(ii), C-(i)
A-(ii), B-(iii), C-(i)

Question 37 of 104

37. Question

The exchange of gases in the alveoli of the lungs takes place by

passive transport
osmosis
active transport
simple diffusion

Question 38 of 104

38. Question

The given figure shows diagrammatic representation of exchange of gases at the alveolus and the body tissues with blood and transport of oxygen and carbon dioxide. Identify the blood vessels A to D.

A-Systemic vein, B- Pulmonary artery, C- Pulmonary vein, D- Systemic artery
A- Systemic artery, B- Pulmonary artery, C- Pulmonary vein, D- Systemic vein
A- Pulmonary artery, B- Systemic vein, C- Pulmonary vein, D- Systemic artery
A- Systemic vein, B- Pulmonary vein, C- Pulmonary artery, D- Systemic artery

Question 39 of 104

39. Question

Consider the following statements each with two blanks.
(i) Diaphragm contracts to help in (1) while the contraction of abdominal muscles help in (2).
(ii) Vital capacity of trained athletes is (3) than that of non-athletes while the vital capacity of non-smokers is (4) than that of smokers.
(iii) Alveolar \(\mathrm{pO}_2\) is (5) than the venous \(\mathrm{pO}_2\) while arterial \(\mathrm{pO}_2\) is (6) than the alveolar \(\mathrm{pO}_2\).
Which of the following options gives the correct fill-ups for the respective blanks numbered from (1) to (6) in the above statements?

(1)-expiration, (2)-inspiration, (5)-higher, (6)-lower
(3)-higher, (4)-lower, (5)-lower, (6)-higher
(1)-inspiration, (2)-forced expiration, (3)-higher, (4)-higher
(1)-expiration, (2)-forced expiration, (5)-higher, (6)-lower

Question 40 of 104

40. Question

Which of the following would have the same \(\mathrm{O}_2\) content?

Blood entering the lungs and blood leaving the lungs
Blood entering the right side of the heart and blood leaving the right side of the heart
Blood entering the right side of the heart and blood leaving the left side of the heart
Blood entering the tissue capillaries and blood leaving the tissue capillaries

Question 41 of 104

41. Question

What is the approximate normal composition of alveolar air?

\(14 \%\) oxygen, \(6 \%\) carbon dioxide, \(80 \%\) nitrogen
\(21 \%\) oxygen, \(2 \%\) carbon dioxide, \(77 \%\) nitrogen
\(16 \%\) oxygen, \(3 \%\) carbon dioxide, \(81 \%\) nitrogen
\(10 \%\) oxygen, \(8 \%\) carbon dioxide, \(82 \%\) nitrogen

Question 42 of 104

42. Question

The \(\mathrm{CO}_2\) content by volume, in the atmospheric air is about

\(3.34 \%\)
\(4 \%\)
\(0.0314 \%\)
\(2.1 \%\)

Question 43 of 104

43. Question

Among the following the partial pressure of oxygen is maximum in

alveolar air
arterial blood
venous blood
expired air

Question 44 of 104

44. Question

In lungs, the air is separated from the venous blood through

transitional epithelium + tunica externa of blood vessel
squamous epithelium + endothelium of blood vessel
squamous epithelium + tunica media of blood vessel
none of these

Question 45 of 104

45. Question

The factor which does not affect the rate of alveolar diffusion is

solubility of gases
thickness of the membranes
pressure gradient
reactivity of the gases

Question 46 of 104

46. Question

Which of the following statements is correct?

The contraction of internal intercostal muscles lifts up the ribs and sternum.
The RBCs transport oxygen only.
The thoracic cavity is anatomically an air tight chamber.
Healthy man can inspire approximately \(500 \mathrm{~mL}\) of air per minute.

Question 47 of 104

47. Question

After taking a long deep breath we do not respire for some seconds due to

more \(\mathrm{CO}_2\) in blood
more \(\mathrm{O}_2\) in blood
less \(\mathrm{CO}_2\) in blood
less \(\mathrm{O}_2\) in blood

Question 48 of 104

48. Question

A large proportion of oxygen remains unused in the human blood even after its uptake by the body tissues. This \(\mathrm{O}_2\)

acts as a reserve during muscular exercise
raises the \(\mathrm{pCO}_2\) of blood to \(75 \mathrm{~mm}\) of \(\mathrm{Hg}\)
is enough to keep oxyhaemoglobin saturation at \(96 \%\)
helps in releasing more \(\mathrm{O}_2\) to the epithelial tissues.

Question 49 of 104

49. Question

Which of the following is true for \(\mathrm{CO}_2\) concentration?

More in alveolar air than in expired air
More in expired air than in alveolar air
More in inspired air than in alveolar air
More in inspired air than in expired air

Question 50 of 104

50. Question

During rest, the metabolic needs of the body are at their minimum. Which of the following is indicative of this situation?

Rate of breathing
\(\mathrm{O}_2\) intake and \(\mathrm{CO}_2\) output
Pulse rate
All of these

Question 51 of 104

51. Question

Consider the following four statements ( i – iv) and select the correct option stating which ones are true (T) and which ones are false (F).
(i) Formation of oxyhaemoglobin occurs on alveolar surface.
(ii) During gaseous exchange the gases diffuse from high partial pressure to low partial pressure.
(iii) Carbon dioxide cannot be transported with haemoglobin.
(iv) Earthworm respires through parapodia.

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } & \text { (iv) } \\
\hline \text { (a) } & \text { T } & \text { F } & \text { T } & \text { F } \\
\hline \text { (b) } & \text { F } & \text { F } & \text { T } & \text { F } \\
\hline \text { (c) } & \text { F } & \text { T } & \text { F } & \text { T } \\
\hline \text { (d) } & \text { T } & \text { T } & \text { F } & \text { F } \\
\hline
\end{array}
\)

a
b
c
d

Question 52 of 104

52. Question

Besides RBC, blood plasma also carries \(\mathrm{O}_2\) in solution. The percentage is

\(3.9 \%\)
\(1-2 \%\)
\(3.6 \%\)
\(2-3 \%\)

Question 53 of 104

53. Question

Which of the following statements is true about RBCs in humans?

They carry about 20-25 percent of \(\mathrm{CO}_2\)
They transport 99.5 percent of \(\mathrm{O}_2\)
They transport about 80 per cent oxygen only and the rest 20 percent of it is transported in dissolved state in blood plasma
They do not carry \(\mathrm{CO}_2\) at all

Question 54 of 104

54. Question

The carbon dioxide is transported via blood to lungs mostly

in combination with haemoglobin only
dissolved in blood plasma
in the form of bicarbonates
as carbaminohaemoglobin

Question 55 of 104

55. Question

Blood carries the \(\mathrm{CO}_2\) in three forms. The correct percentages of \(\mathrm{CO}_2\) in these forms are

\(
\begin{array}{|l|l|l|l|}
\hline & \begin{array}{l}
\text { As carbamino- } \\
\text { haemoglobin in RBC }
\end{array} & \begin{array}{l}
\text { As } \\
\text { bicarbonates }
\end{array} & \begin{array}{l}
\text { Dissolved form in } \\
\text { plasma }
\end{array} \\
\hline \text { (a) } & 20-25 \% & 70 \% & 7 \% \\
\hline \text { (b) } & 70 \% & 20-25 \% & 7 \% \\
\hline \text { (c) } & 20-25 \% & 7 \% & 70 \% \\
\hline \text { (d) } & 7 \% & 20-25 \% & 70 \% \\
\hline
\end{array}
\)

a
b
c
d

Question 56 of 104

56. Question

Bulk of oxygen diffuses from the plasma into the red blood corpuscles where it joins loosely with \(\mathrm{Fe}^{2+}\) ions of haemoglobin \((\mathrm{Hb})\) to form bright red oxyhaemoglobin \(\left(\mathrm{HbO}_2\right)\). This process is called

oxidation
hydration
oxygenation
dehydrogenation

Question 57 of 104

57. Question

How many molecules of \(\mathrm{O}_2\) does one haemoglobin carries?

4
2
6
8

Question 58 of 104

58. Question

The oxygen dissociation curve is

parabola
slope
sigmoid
straight line

Question 59 of 104

59. Question

Which of the following is incorrect about the given graph?

The curve is called oxygen dissociation curve.
The part ‘ \(A\) ‘ represents percentage saturation of haemoglobin with oxygen.
The part ‘ \(B\) ‘ represents partial pressure of carbon dioxide.
This curve is highly useful in studying the effect of factors like \(\mathrm{pCO}_2, \mathrm{H}^{+}\)concentration, etc. on binding of \(\mathrm{CO}_2\) with haemoglobin.

Question 60 of 104

60. Question

The given graph shows an oxygen dissociation curve for haemoglobin.

Where in the body will haemoglobin be saturated at the percentages shown at points 1,2 and 3 on the graph?

\(
\begin{array}{lccc}
& \text { Left ventricle } & \text { Pulmonary vein } & \text { Vena cava } \\
\text { (a) } & 1 & 2 & 3 \\
\text { (b) } & 2 & 1 & 3 \\
\text { (c) } & 2 & 3 & 1 \\
\text { (d) } & 3 & 2 & 1
\end{array}
\)

a
b
c
d

Question 61 of 104

61. Question

When temperature decreases, oxy-Hb curve becomes

more steep
straight
parabola
none of these

Question 62 of 104

62. Question

Which of the following factors is not favourable for the formation of oxyhaemoglobin?

High \(\mathrm{pO}_2\)
Low temperature
Less \(\mathrm{H}^{+}\)concentration
High \(pCO_2\)

Question 63 of 104

63. Question

63Consider the following four statements and select the correct option stating which ones are true (T) and which ones are false (F).
(i) Expiration is normally brought about by the relaxation of inspiratory muscles.
(ii) Oxyhaemoglobin can hold much less carbon dioxide in the form of carbaminohaemoglobin than what deoxyhaemoglobin can.
(iii) A person can expel all the air from the lungs by a forceful expiration.
(iv) A rise in \(\mathrm{PCO}_2\) increases the oxygen-affinity of haemoglobin.

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } & \text { (iv) } \\
\hline \text { (a) } & \text { F } & \text { F } & \text { T } & \text { T } \\
\hline \text { (b) } & \text { T } & \text { F } & \text { T } & \text { T } \\
\hline \text { (c) } & \text { T } & \text { T } & \text { F } & \text { F } \\
\hline \text { (d) } & \text { F } & \text { F } & \text { F } & \text { T } \\
\hline
\end{array}
\)

a
b
c
d

Question 64 of 104

64. Question

In the tissues, high concentrations of carbon dioxide

increases the affinity of haemoglobin to both oxygen and hydrogen
increases the affinity of haemoglobin to oxygen but decreases its affinity to hydrogen
decreases the affinity of haemoglobin to oxygen but increases its affinity to hydrogen
decreases the affinity of haemoglobin to both oxygen and hydrogen

Question 65 of 104

65. Question

Fetal haemoglobin has \(X\) affinity for oxygen than that of mother’s haemoglobin during gestation. \(X\) is

same
higher
lower
lower affinity earlier but higher later

Question 66 of 104

66. Question

Read the given statements and select the correct option.

Statement 1: About \(70 \%\) of \(\mathrm{CO}_2\) that enters RBCs changes into \(\mathrm{HCO}_3^{-}\)for transport in plasma to the lungs where it reconverts into \(\mathrm{CO}_2\) for elimination.
Statement 2: About \(40 \%\) of \(\mathrm{CO}_2\) that enters RBCs changes into carbaminohaemoglobin which releases \(\mathrm{O}_2\) in the lungs.

Both statements 1 and 2 are correct.
Statement 1 is correct but statement 2 is incorrect.
Statement 1 is incorrect but statement 2 is correct.
Both statements 1 and 2 are incorrect.

Question 67 of 104

67. Question

Match column I with column II and select the correct option from the codes given below.

\(
\begin{array}{|c|l|c|l|}
\hline & \text { Column I } & & \text { Column II } \\
\hline \text { A. } & \text { Tracheoles } & \text { (i) } & \text { Yeast } \\
\hline \text { B. } & \text { Carbonic anhydrase } & \text { (ii) } & \text { Fish } \\
\hline \text { C. } & \text { Lactic acid } & \text { (iii) } & \text { Inspiration } \\
\hline \text { D. } & \text { Fermentation } & \text { (iv) } & \text { Vital capacity } \\
\hline \text { E. } & \text { Gill filaments } & \text { (v) } & \text { Fast muscle } \\
\hline \text { F. } & \text { Cutaneous respiration } & \text { (vi) } & \text { Insect } \\
\hline \text { G. } & \text { Diaphragm } & \text { (vii) } & \text { Bicarbonates } \\
\hline & & \text { (viii) } & \text { Earthworm } \\
\hline
\end{array}
\)

A-(vi), B-(vii), C-(v), D-(i), E-(ii), F-(viii), G-(iii)
A-(viii), B-(iv), C-(vii), D-(i), E-(iii), F-(ii), G-(v)
A-(vi), B-(i), C-(ii), D-(v), E-(iv), F-(viii), G-(iii)
A-(viii), B-(vii), C-(i), D-(iv), E-(ii), F-(vi), G-(v)

Question 68 of 104

68. Question

The enzyme that increases the reaction rate between \(\mathrm{CO}_2\) and \(\mathrm{H}_2 \mathrm{O}\) in red blood cells is

carbonic anhydrase
carbonic synthetase
adenylate cyclase
alkaline phosphatase

Question 69 of 104

69. Question

Which of the following equations is correct?

\(\mathrm{CO}_2 \longrightarrow \mathrm{H}_2 \mathrm{CO}_3 \longrightarrow \mathrm{HCO}_3^{-}+\mathrm{H}^{+}\)
\( \mathrm{CO}_2+\mathrm{H}_2 \mathrm{O} \underset{\text { anhydrase }}{\stackrel{\text { Carbonic }}{\rightleftharpoons}} \mathrm{H}_2 \mathrm{CO}_3 \underset{\text { anhydrase }}{\stackrel{\text { Carbonic }}{\rightleftarrows}} \mathrm{H}^{+}+\mathrm{HCO}_3^{-} \)
\( \mathrm{CO}_2+\mathrm{H}_2 \mathrm{O} \longrightarrow \mathrm{CH}_4+2 \mathrm{O}_2 \)
\( \mathrm{CO}_2+\mathrm{H}_2 \mathrm{O} \rightleftharpoons \mathrm{CO}+\mathrm{H}_2 \mathrm{O}_2 \)

Question 70 of 104

70. Question

People living at sea level have around 5 million RBC per cubic millimetre of their blood whereas those living at an altitude of 5400 metres have around 8 million. This is because at high altitude

people eat more nutritive food, therefore more RBCs are formed
people get pollution-free air to breathe and more oxygen is available
atmospheric \(\mathrm{O}_2\) level is less and hence more RBCs are needed to absorb the required amount of \(\mathrm{O}_2\) to survive
there is more UV radiation which enhances RBC production.

Question 71 of 104

71. Question

Identify the correct statement with reference to transport of respiratory gases by blood.

Haemoglobin is necessary for transport of carbon dioxide and carbonic anhydrase for transport of oxygen.
Haemoglobin is necessary for transport of oxygen and carbonic anhydrase for transport of carbon dioxide.
Only oxygen is transported by blood.
Only carbon dioxide is transported by blood.

Question 72 of 104

72. Question

In humans, which of the following is not a step in respiration?

Alveolar diffusion of \(\mathrm{O}_2\) and \(\mathrm{CO}_2\)
Transport of gases by blood
Diffusion of \(\mathrm{O}_2\) and \(\mathrm{CO}_2\) between blood and tissues
Utilisation of \(\mathrm{CO}_2\) by cells for catabolic reactions

Question 73 of 104

73. Question

Although much \(\mathrm{CO}_2\) is carried in blood, yet blood does not become acidic, because

\(\mathrm{CO}_2\) is absorbed by the leucocytes
oxygen combines with haemoglobin to form oxyhaemoglobin
\(\mathrm{CO}_2\) transport and blood buffers play an important role in it
it is continuously diffused through the tissues and is not allowed to accumulate.

Question 74 of 104

74. Question

Which one of the following can bind several hundred times more strongly to the haemoglobin than oxygen?

\(\mathrm{H}_2 \mathrm{CO}_3\)
\(\mathrm{CO}_2\)
\(\mathrm{CO}\)
None of these

Question 75 of 104

75. Question

Select the correct statement.

Human RBC transport 98 percent of \(\mathrm{O}_2\).
Human \(\mathrm{RBC}\) transport 20.25 percent of \(\mathrm{CO}_2\).
Majority of \(\mathrm{CO}_2\) is transported to the lungs as attached to haemoglobin.
All of these.

Question 76 of 104

76. Question

Match column I with column II and select the correct option from the given codes.

\(
\begin{array}{|c|c|c|c|}
\hline & \text { Column I } & & \text { Column II } \\
\hline \text { A. } & \text { Trachea } & \text { (i) } & \mathrm{pO}_2 \text { in alveolar air } \\
\hline \text { B. } & \text { Respiratory centre } & \text { (ii) } & \text { ATP } \\
\hline \text { C. } & \text { Yeast } & \text { (iii) } & \text { Cartilaginous rings } \\
\hline \text { D. } & \text { Pigeon } & \text { (iv) } & \text { Medulla oblongata } \\
\hline \text { E. } & \text { Fish } & \text { (v) } & \text { Larynx } \\
\hline \text { F. } & \begin{array}{l}
\text { Biologically useful } \\
\text { energy }
\end{array} & \text { (vi) } & \text { Lungs } \\
\hline \text { G. } & 100 \mathrm{~mm} \mathrm{Hg} & \text { (vii) } & \text { Ethanol } \\
\hline \mathrm{H} \text {. } & \text { Vocal cords } & \text { (viii) } & \text { Branchial respiration } \\
\hline
\end{array}
\)

A-(iii), B-(iv), C-(vii), D-(vi), E-(viii), F-(ii), G-(i), H-(v)
A-(v), B-(ii), C-(vii), D-(viii), E-(vi), F-(iv), G-(i), H-(iii)
A-(vi), B-(iv), C-(viii), D-(v), E-(i), F-(ii), G-(iii), H-(vii)
A-(i), B-(v), C-(vii), D-(iii), E-(viii), F-(ii), G-(iv), H-(vi)

Question 77 of 104

77. Question

Pneumotaxic centre which can moderate the functions of the respiratory rhythm centre is present in

pons region of brain
thalamus
spinal cord
right cerebral hemisphere

Question 78 of 104

78. Question

Match column I with column II and select the correct option from the codes given below.

\(
\begin{array}{|l|l|c|l|}
\hline & \text { Column I } & & \text { Column II } \\
\hline \text { A. } & \begin{array}{l}
\text { Carbamino- } \\
\text { haemoglobin }
\end{array} & \text { (i) } & \text { Inspiration } \\
\hline \text { B. } & \text { Diaphragm } & \text { (ii) } & \text { Hamburger’s phenomenon } \\
\hline \text { C. } & \text { Larynx } & \text { (iii) } & \text { Diffusion of } \mathrm{Cl}^{-} \text {into } \mathrm{RBCs} \\
\hline \text { D. } & \text { Pons varolii } & \text { (iv) } & \text { Carbon dioxide } \\
\hline \text { E. } & \text { Chloride shift } & \text { (v) } & \text { Cartilages } \\
\hline & & \text { (vi) } & \text { Pneumotaxic centre } \\
\hline & & \text { (vii) } & \text { Expiration } \\
\hline
\end{array}
\)

A-(iv); B-(i), (vii); C-(v); D-(vi); E-(ii), (iii)
A-(v); B-(i); C-(iv), (vii); D-(vi); E-(ii), (iii)
A-(ii), (vi); B-(i);C-(iii); D-(v), (vii); E-(iv)
A-(iii); B-(i); C-(ii),(v); D-(vi), (vii); E-(iv)

Question 79 of 104

79. Question

Chemosensitive area of respiratory centre in medulla is affected by

less \(\mathrm{CO}_2\) and \(\mathrm{H}^{+}\)ions
less \(\mathrm{O}_2\) and \(\mathrm{H}^{+}\)ions
excess \(\mathrm{CO}_2\) and \(\mathrm{H}^{+}\)ions
excess \(\mathrm{O}_2\) and \(\mathrm{H}^{+}\)ions

Question 80 of 104

80. Question

Fill up the blanks in the following paragraph by selecting the correct option.
Human beings have a significant ability to maintain and moderate the respiratory rhythm to suit the demands of the body tissues. This is done by the neural system. A specialised centre present in the medulla region of the brain called (i) is primarily responsible for this regulation. Another centre present in the pons region of the brain called (ii) can moderate the functions of the respiratory rhythm centre. Neural signal from this centre can reduce the duration of (iii) and thereby alter the respiratory rate. A (iv) is situated adjacent to the rhythm centre which is highly sensitive to \(\mathrm{CO}_2\) and hydrogen ions.

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } & \text { (iv) } \\
\hline \text { (a) } & \begin{array}{l}
\text { Chemosensitive } \\
\text { area }
\end{array} & \begin{array}{l}
\text { Respiratory } \\
\text { rhythm centre }
\end{array} & \text { Expiration } & \begin{array}{l}
\text { Pneumotaxic } \\
\text { centre }
\end{array} \\
\hline \text { (b) } & \begin{array}{l}
\text { Respiratory } \\
\text { rhythm centre }
\end{array} & \begin{array}{l}
\text { Pneumotaxic } \\
\text { Centre }
\end{array} & \text { Inspiration } & \begin{array}{l}
\text { Chemosensitive } \\
\text { area }
\end{array} \\
\hline \text { (c) } & \begin{array}{l}
\text { Respiratory } \\
\text { rhythm centre }
\end{array} & \begin{array}{l}
\text { Chemosensitive } \\
\text { area }
\end{array} & \text { Expiration } & \begin{array}{l}
\text { Pneumotaxic } \\
\text { centre }
\end{array} \\
\hline \text { (d) } & \begin{array}{l}
\text { Pneumotaxic } \\
\text { centre }
\end{array} & \begin{array}{l}
\text { Chemosensitive } \\
\text { area }
\end{array} & \text { Inspiration } & \begin{array}{l}
\text { Respiratory } \\
\text { rhythm centre }
\end{array} \\
\hline
\end{array}
\)

a
b
c
d

Question 81 of 104

81. Question

Rate of breathing is controlled mainly by

\(\mathrm{CO}_2\) level in blood
\(\mathrm{pH}\) in blood
\(\mathrm{O}_2\) level in blood
\(\mathrm{O}_2\) level and \(\mathrm{pH}\) in blood.

Question 82 of 104

82. Question

The respiratory centre in the brain is stimulated by

\(\mathrm{CO}_2\) concentration in venous blood
\(\mathrm{O}_2\) concentration in arterial blood
\(\mathrm{CO}_2\) concentration in arterial blood
\(\mathrm{O}_2\) concentration in venous blood.

Question 83 of 104

83. Question

Complete the following sentence by selecting the correct option.
Receptors associated with the aortic arch and carotid artery can recognise changes in (i) and (ii) concentration and send necessary signals to (iii) for remedial actions.

\(
\begin{array}{|l|l|l|l|}
\hline & \text { (i) } & \text { (ii) } & \text { (iii) } \\
\hline \text { (a) } & \mathrm{O}_2 & \mathrm{CO}_2 & \text { pneumotaxic centre } \\
\hline \text { (b) } & \mathrm{CO}_2 & \mathrm{H}^{+} & \text {rhythm centre } \\
\hline \text { (c) } & \mathrm{CO}_2 & \mathrm{H}^{+} & \text {apneustic centre } \\
\hline \text { (d) } & \mathrm{O}_2 & \mathrm{H}^{+} & \text {pneumotaxic centre } \\
\hline
\end{array}
\)

a
b
c
d

Question 84 of 104

84. Question

Complete the following sentence by selecting the correct option.
The breathing rhythm is generated in the (i) and is influenced by variation in levels of (ii) in the blood.

\(
\begin{array}{|l|l|l|}
\hline & \text { (i) } & \text { (ii) } \\
\hline \text { (a) } & \text { medulla } & \mathrm{CO}_2 \\
\hline \text { (b) } & \text { medulla } & \mathrm{O}_2 \\
\hline \text { (c) } & \text { frontal lobe } & \mathrm{CO}_2 \text { and } \mathrm{O}_2 \\
\hline \text { (d) } & \text { frontal lobe } & \mathrm{CO}_2 \\
\hline
\end{array}
\)

a
b
c
d

Question 85 of 104

85. Question

When \(\mathrm{CO}_2\) concentration in blood increases breathing becomes

shallower and slow
there is no effect on breathing
slow and deep
faster and deeper

Question 86 of 104

86. Question

Read the given statements and select the correct option.
Statement 1: Rate of breathing is regulated by respiratory centres present in the medulla oblongata.
Statement 2: Changes in the \(\mathrm{CO}_2\) level of the arterial blood control the rate of breathing.

Both statements 1 and 2 are correct.
Statement 1 is correct but statement 2 is incorrect.
Statement 1 is incorrect but statement 2 is correct.
Both statements 1 and 2 are incorrect.

Question 87 of 104

87. Question

Read the following four statements (i) – (iv) with certain mistakes in two of them.
(i) A water breather expends much more energy in ventilating its respiratory surface than an airbreathing one.
(ii) Lungs become empty after forceful expiration.
(iii) The exchange of gases in the lungs is interrupted during expiration.
(iv) Respiratory movements are controlled by \(\mathrm{CO}_2\) concentration of arterial blood.
Which of the above two statements have mistakes?

(i) and (iv)
(ii) and (iii)
(i) and (ii)
(iii) and (iv)

Question 88 of 104

88. Question

The urge to inhale in humans results from

rising \(\mathrm{pCO}_2\)
falling \(\mathrm{pCO}_2\)
rising \(\mathrm{pO}_2\)
falling \(\mathrm{pO}_2\)

Question 89 of 104

89. Question

Read the following four statements carefully.
(i) Ventral respiratory group of neurons of medulla oblongata can cause both inspiration and expiration.
(ii) The part of the respiratory system starting with the external nostrils up to the terminal bronchioles constitutes the respiratory or exchange part of the respiratory system.
(iii) During swallowing epiglottis can be covered by a thin elastic cartilaginous flap called glottis to prevent the entry of food into the larynx.
(iv) Binding of oxygen with haemoglobin is primarily related to partial pressure of \(\mathrm{O}_2\).
Which of the above two statements are correct?

(ii) and (iii)
(i) and (ii)
(iii) and (iv)
(i) and (iv)

Question 90 of 104

90. Question

Emphysema is a condition resulting from

cigarette smoking
liquor consumption
drug addiction
reduced oxygen carrying capacity of blood

Question 91 of 104

91. Question

Which one of the following is the incorrect statement for respiration in humans?

Cigarette smoking may lead to inflammation of bronchi.
Neural signals from pneumotaxic centre in pons region of brain can increase the respiratory rate.
Workers in grinding and stone-breaking industries may suffer from lung fibrosis.
None of these

Question 92 of 104

92. Question

Name the pulmonary disease in which alveolar surface area involved in gas exchange is drastically reduced due to damage in the alveolar walls.

Pneumonia
Pleurisy
Asthma
Emphysema

Question 93 of 104

93. Question

Visiting high mountains may cause altitude sickness in men living in plain areas. Prime cause of this is

excess of \(\mathrm{CO}_2\) in blood
decreased efficiency of haemoglobin
decreased partial pressure of oxygen
decreased efficiency of red blood cells

Question 94 of 104

94. Question

Carbon monoxide can kill a person because of it’s extremely high affinity for

haemoglobin
phytochrome
cytochrome
none of these

Question 95 of 104

95. Question

Asthma may be attributed to

inflammation of the trachea
accumulation of fluid in the lungs
bacterial infection of the lungs
allergic reaction of the mast cells in the lungs

Question 96 of 104

96. Question

Blood analysis of a patient reveals an unusually high quantity of carboxyhaemoglobin content. Which of the following conclusions is most likely to be correct?
The patient has been inhaling polluted air containing unusually high content of

carbon disulphide
chloroform
carbon monoxide
none of these

Question 97 of 104

97. Question

During winter a person died during sleep, the room was closed and a container with burnt charcoal was found in the room. What may be the possible reason of his death?

Non-availability of carbon dioxide
\(\mathrm{Hb}\) has more affinity to combine with carbon monoxide
\(\mathrm{Hb}\) has more affinity to combine with carbon dioxide
Combined effect of both (a) and (b)

Question 98 of 104