Tag: respiratory system of human

Questions Related to respiratory system of human

The inspiratory reserve volume is also known as 

  1. Supplemental air

  2. Inhaled air

  3. Complemental air

  4. All of the above


Correct Option: C
Explanation:

During one breath in and out, the volume of gas exchanged is called the tidal volume. It is about 450ml during quiet breathing. The volume of air that can be drawn in after normal inspiration is about 1500 ml and is called as the inspiratory reserve volume (IRV) or complemental air.

Therefore, the correct answer is option C.

The relationship between pressure and volume was first noted by ............. while ............. confirmed their discovery and ............ published the result.

  1. Richard Towneley and Henry Power, Robert Boyle

  2. Richard Towneley and Henry Power, Robert Hooke

  3. Robert Boyle and Robert Hooke, Robert Boyle

  4. None of these


Correct Option: A
Explanation:
  • Boyle's law (sometimes referred to as the Boyle–Mariotte law or Mariotte's law is an experimental gas law that describes how the pressure of a gas tends to increase as the volume of the container decreases. A modern statement of Boyle's law is - The absolute pressure exerted by a given mass of an ideal gas is inversely proportional to the volume it occupies if the temperature and amount of gas remain unchanged within a closed system.
  • This relationship between pressure and volume was first noted by Richard Towneley and Henry Power in the seventeenth century. Robert Boyle confirmed their discovery through experiments and published the results. So, the correct answer is A.

In man expired air contains oxygen about

  1. 4%

  2. 10%

  3. 16%

  4. 20%


Correct Option: C
Explanation:

A man exhaled the air almost equivalent to the mixture of the atmosphere which contains 78% nitrogen, 16% oxygen, 0.09% argon and 4% carbon dioxide.

So the correct option is '16%'.

According to Boyle's law, the product of:.pressure and volume is a constant. Hence,

  1. if volume of lungs is increased, then pressure decreases proportionately

  2. if volume of lungs is increased, then pressure also increases proportionately

  3. if volume of lungs is increased, then pressure decreases disproportionately

  4. if volume of lungs is increased, then pressure remains the same.


Correct Option: A
Explanation:
According to Boyle's law, the product of pressure and volume is a constant. Hence, if the volume of the lungs is increased, then pressure decreases proportionately.
So, the correct answer is 'if volume of lungs is increased, then pressure decreases proportionately'.

Which of the following is true regarding expiration?

  1. Exhaled air contains more moisture

  2. Lungs are not completely emptied even after forciful exhalation

  3. Exchange of gases takes place during expiration

  4. All of the above


Correct Option: D
Explanation:

  • Expiration is a mechanism in which air which contains carbon dioxide release out from the lungs of the body.
  • This air is dry and contains more moisture from the lungs.
  • Lungs can never be empty even after force full expiration some amount of air remains in it known as residual volume.
  • The exchange of gases occurs only at cellular and alveolar site, not in expiration.
So the correct option is 'Both A and B'.

During inspiration, the diaphragm 

  1. Expands

  2. Shows no change

  3. Contracts and flattens

  4. Relaxed to become dome shaped


Correct Option: C
Explanation:

During inspiration, the diaphragm contracts and flattens to increase the volume of the the thoracic cavity. This increase in volume leads to a decrease in intra-alveolar pressure, which is a pressure lower than atmospheric pressure and creates the pressure gradient. Due to the gradient the air is from the atmosphere is forced inside the lungs through nasal cavity.

So, the correct answer is 'Contracts and flattens'.

Which of the following does not happen during exhalation?

  1. The space in chest cavity decreases

  2. Diaphragm goes up

  3. Air is released

  4. Ribs are pushed upward and outward


Correct Option: D
Explanation:
  • During exhalation diaphragm relaxes. 
  • The intercoastal muscles also relax.
  • This makes ribs to move down and in.
  • It reduces the volume of the chest cavity and the air is pushed out
So, the correct option is 'Ribs are pushed upward and outward'.

In males, ______ play a role in the movement of respiratory system.

  1. Vertebrae

  2. Sternum

  3. Diaphragm

  4. Liver


Correct Option: C
Explanation:

The diaphragm is the muscular organ situated between the thoracic cavity and the abdominal cavity. It contracts and moves downwards due to which the volume in the lungs increases and the air is inhaled. When it relaxes, the volume of the lungs decreases and the air is expelled out.

A. The vertebra is the short bone that makes up the vertebral column.
B. The sternum is the breastbone to which the ribs are attached.
C. The diaphragm is the muscular organ that plays role in the movement of the respiratory system.
D. The liver is the largest gland responsible for various metabolic activities.
Hence, the correct answer is 'Diaphragm'.

The exchange of gases between which of the following is called external respiration?

  1. Lung alveoli and blood capillaries

  2. Lung alveoli and bronchi

  3. The buccal cavity and the external atmosphere

  4. Lung alveoli and pulmonary artery


Correct Option: A
Explanation:

When the gaseous exchange occurs due to a difference in the partial pressure of gases between alveoli of lungs and capillaries it is termed as an external exchange as it involves air that ix either inhaled or exhaled from the environment outside the body while when the exchange occurs between capillaries and tissue it is known as the internal exchange.

So the correct option is 'Lung alveoli and blood capillaries'.

Which of the following is the correct path of oxygen in humans during inhalation?

  1. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Pharynx $\rightarrow$ Trachea $\rightarrow$ Bronchi $\rightarrow$ Bronchiole $\rightarrow$ Alveoli

  2. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Trachea $\rightarrow$ Pharynx $\rightarrow$ Bronchi $\rightarrow$ Bronchiole $\rightarrow$ Alveoli

  3. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Pharynx $\rightarrow$ Trachea $\rightarrow$ Alveoli $\rightarrow$ Bronchi $\rightarrow$ Bronchiole

  4. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Pharynx $\rightarrow$ Bronchi $\rightarrow$ Trachea $\rightarrow$ Bronchioles $\rightarrow$ Alveoli


Correct Option: A
Explanation:
The correct path of oxygen transfer is nostrils - external structures, nasal passage or the nasal cavity then into the pharynx followed by trachea and bronchii to smaller branches called the bronchioles and lastly the alveoli from where it is exchanged into the blood stream with the help of capillaries surrounding the alveoli.
So, the correct answer is Nostrils Nasal Cavity Pharynx Trachea Bronchi Bronchiole Alveoli