Breathing and Exchange of Gases NCERT

Name the cavities in which the lungs are located:

A minimal amount of pleural fluid present in the pleural cavity:

Branchial respiration is seen in all the following except:

The conducting part of the human respiratory system is not involved in:
I. Clearing inhaled air from foreign particles
II. Humidifying the exhaled air
III. Bringing the air to a temperature higher than body temperature

Incomplete cartilaginous rings are seen in the walls of all the following except:

The given figure shows the diagrammatic view of human respiratory system (sectional view of the left lung is also shown). Regarding the parts labelled as P , Q , R and S , which of the following statements are true?

I:  P is an incomplete cartilaginous ring seen only in trachea and principal bronchus. 
II:  Q is the point where the trachea divides into a right and left primary bronchus and corresponds to the level of 5th thoracic vertebra. 
III: R shows the double-layered pleura where the outer pleural membrane is in close contact with the thoracic lining. 
IV:  S is pleural cavity with minimal amount of pleural fluid which reduces friction on the lung surface.

Consider the following two statements:
I. The lungs are situated in the thoracic chamber which is anatomically an air-tight chamber.
II. This arrangement is essential as we cannot directly alter the thoracic volume.

Consider the given two statements:
I: Lower invertebrates like sponges, coelenterates and flatworms exchange oxygen with carbon dioxide by simple diffusion over their entire body surface.
II: Fishes are the only vertebrates that do not use lungs as respiratory organs.

It is necessary that lungs must be present in anatomically air-tight chamber because:

Which of the following is not correctly matched ?

\(
\begin{array}{|l|l|l|}
\hline \hline \text { I. } & \begin{array}{l}
\text { Thoracic chamber is formed dorsally } \\
\text { by }
\end{array} & \text { Sternum } \\
\hline \text { II. } & \begin{array}{l}
\text { Thoracic chamber is formed ventrally } \\
\text { by }
\end{array} & \begin{array}{l}
\text { Vertebral } \\
\text { column }
\end{array} \\
\hline \text { III. } & \begin{array}{l}
\text { Thoracic chamber is formed laterally } \\
\text { by }
\end{array} & \text { Ribs } \\
\hline \text { IV. } & \begin{array}{l}
\text { Thoracic chamber is formed on the } \\
\text { lower side by }
\end{array} & \text { Diaphragm } \\
\hline
\end{array}
\)

The figure shows the events happening during the inhalation and exhalation phases of pulmonary ventilation. Read the two given statements carefully.

I:- A shows the inhalation phase brought about by the contraction of diaphragm that increases the volume of thorax in antero-posterior axis and by the contraction of external intercostal muscle that increases the volume of thorax in dorso-ventral axis.
II:- B shows the exhalation phase brought about by the relaxation of diaphragm that decreases the volume of thorax in antero-posterior axis and by the contraction of internal intercostal muscle that decreases the volume of thorax in dorso-ventral axis.

Regarding pulmonary capacities, the maximum volume of air a person can breathe in after a forced expiration can also be defined as:

In inspiration during pulmonary ventilation the correct order of the given events is:
a. air flows into the lungs
b. alveolar volume increases
c. thoracic volume increases
d. pleural pressure decreases
e. alveolar pressure decreases

Consider the given two statements:
I: Relaxation of the diaphragm and the intercostal muscles causes the expulsion of air from the lungs.
II: Relaxation of the diaphragm and the intercostal muscles increases the volume of thoracic chamber in the antero-posterior axis.

Both carbon dioxide and oxygen move across the respiratory membrane due to:

With respect to the atmospheric air, the deoxygenated blood flowing into lung capillaries has a higher concentration of:

Exchange of gases occurs across the respiratory membrane. Which of the following would increase the rate of diffusion of a gas across the respiratory membrane?

When compared with carbon dioxide, the partial pressure of oxygen in the air and its solubility in water is respectively:

The value of partial pressure of oxygen in alveolar air is:

Carbon dioxide is transported in blood by all the following mechanisms except:

I:   The partial pressures of Oxygen and Carbon dioxide at Point A in Figure I correspond to that of Point P in Figure II.

II:  The partial pressure of Carbon dioxide at Point B in Figure I corresponds to that of Point Q in Figure II.

Identify the incorrect statement regarding the enzyme carbonic anhydrase:

The binding of carbon dioxide to hemoglobin:
I. is related to the partial pressure of carbon dioxide
II. is affected by the partial pressure of oxygen

The major mode of transport of carbon dioxide in human body is:

Which of the following is higher in value?

Study the oxygen-haemoglobin dissociation curve given in the figure and select the correct statements regarding it:

Study the oxygen-haemoglobin dissociation curve given in the figure and select the correct statements regarding it:
I: The p50 is the pressure at which haemoglobin is \( 50 \% \) saturated which corresponds to about 27 mmHg on the Xaxis.
II: A right shift of the curve means haemoglobin holds less tightly onto oxygen and delivers more oxygen to the tissues at a given arterial oxygen pressure.

The duration of inspiration can be reduced by:

A condition in which a person’s airways become inflamed, narrow, swell and produce extra mucus, which makes it difficult to breathe is known as

Pulmonary fibrosis is a pathological hallmark of:

Which of the following is incorrect regarding emphysema?

Study the given figure showing the neural regulation of respiration in humans and select the correct statements from the given statements.

Statement I: The location of the pneumotaxic centre is the Pons of the brain stem and it moderates the function of respiratory rhythm centre.
Statement II: The respiratory rhythm centre is the dorsal respiratory group shown in the figure and is also located in the Pons of the brain stem.

Assertion: Oxidized hemoglobin carries maximum oxygen in the human blood.
Reason: Oxidized hemoglobin has more affinity for oxygen than deoxygenated hemoglobin.

Identify the respiratory disorder shown in the figure above:

What is true about RBCs in humans?

Oxygen binding to haemoglobin in blood is

Identify the wrong statement with reference to the transport of oxygen.

Why would hemoglobin deliver oxygen to the tissues?

The respiratory system does not:

The diffusion of gases in lungs occur across the respiratory membrane. Which of the following is incorrect regarding the respiratory membrane?

Oxygenated blood through the tissues of the lungs is carried by:

Match the following columns and select the correct option :

\(
\begin{array}{|l|l|l|l|}
\hline & \text { Column I } & & \text { Column II } \\
\hline \text { (a) } & \text { Pneumotaxic centre } & \text { (i) } & \text { Alveoli } \\
\hline \text { (b) } & \mathrm{O}_2 \text { dissociation curve } & \text { (ii) } & \begin{array}{l}
\text { Pons region of the } \\
\text { brain }
\end{array} \\
\hline \text { (c) } & \text { Carbonic anhydrase } & \text { (iii) } & \text { Haemoglobin } \\
\hline \text { (d) } & \begin{array}{l}
\text { Primary site of exchange of } \\
\text { gases }
\end{array} & \text { (iv) } & \text { R.B.C. } \\
\hline
\end{array}
\)

Options:-

\(
\begin{array}{|l|l|l|l|l|}
\hline & \text { (a) } & \text { (b) } & \text { (c) } & \text { (d) } \\
\hline 1 . & \text { (i) } & \text { (iii) } & \text { (ii) } & \text { (iv) } \\
\hline 2 . & \text { (ii) } & \text { (iii) } & \text { (iv) } & \text { (i) } \\
\hline 3 . & \text { (iii) } & \text { (ii) } & \text { (iv) } & \text { (i) } \\
\hline 4 . & \text { (iv) } & \text { (i) } & \text { (iii) } & \text { (ii) } \\
\hline
\end{array}
\)

The pulmonary function of a person reveals the following values:
a. tidal volume = 500 mL
b. residual volume = 1000 mL
c. inspiratory reserve volume = 2500 mL
d. expiratory reserve volume = 1000 mL.

His Vital Capacity:

Consider the following statements:
I. The thoracic chamber is anatomically an air tight chamber.
II. Any change in the volume of the thoracic cavity will be reflected in the pulmonary cavity.

Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because

From the following statements select the correct option/s
(a) Gills are special vascularized structures used by most of the aquatic animals
(b) Lungs are used by the terrestrial forms for the exchange of gases.
(c) Frogs can respire through their moist skin.
(d) Sound box in human is made up of cartilages & bones