Biology

Respiration and Gas Exchange

958 Questions

Access a targeted set of questions on respiration and gas exchange for competitive exams. Topics include lung volumes, the mechanism of breathing, and respiratory anatomy. Understanding these physiological processes is essential for scoring well.

Lung volumes and capacitiesBreathing mechanismsRespiratory anatomyGas exchange processes

Respiration and Gas Exchange Questions

Multiple choice biology human body respiration in humans mechanism of respiration in animals human lungs

If the lung were punctured, which of the following would happen?

  1. The lung would collapse on the side of the puncture.

  2. Both the lung and the chest wall would collapse on the side of the puncture.

  3. Inspiratory signals from medulla become irregular

  4. Interpleural pressure decrease further
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

If the lung is punctured, the intrapleural space is exposed to atmospheric pressure. This eliminates the negative pressure that keeps the lung inflated, causing the lung to collapse (pneumothorax).

Multiple choice biology human body respiration in humans mechanism of respiration in animals human lungs

Which one of the following statements is incorrect?

  1. The residual air in lungs slightly decreases the efficiency of respiration in mammals

  2. The presence of non-respiratory air sacs, increases the efficiency of respiration in birds

  3. In insects, circulating body fluids serve to distribute oxygen to tissues

  4. The principle of counter current flow facilities efficient respiration in gills of fishes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Residual air in the lungs is essential to keep the alveoli from collapsing between breaths; it does not decrease the efficiency of respiration but rather maintains structural integrity. The other statements correctly describe respiratory adaptations in birds, insects, and fish.

Multiple choice biology human body respiration in humans mechanism of respiration in animals human lungs

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

  1. Pressure in the lungs is higher than the atmospheric pressure

  2. There is negative pressure in the lungs

  3. There is negative intrapleural pressure pulling at the lung walls

  4. There is positive intrapleural pressure
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The lungs remain inflated because the intrapleural pressure is lower than the intrapulmonary pressure (negative pressure), which pulls the lungs outward against the chest wall, preventing collapse.

Multiple choice biology human body respiration in humans mechanism of respiration in animals human lungs

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

  1. intrapulmonary pressure is less than the atmospheric pressure

  2. intrapulmonary pressure is greater than the atmospheric pressure

  3. intrapulmonary pressure is equal to the atmospheric pressure

  4. intrapleural pressure becomes more than the intra-alveolar pressure.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Because of the pressure gradient between the lungs and the atmosphere, the air moves into and out of the lungs. Inspiration occurs if the pressure within the lungs (intra-pulmonary pressure) is less than the atmospheric pressure i.e. there is a negative pressure in the lungs with respect to atmospheric pressure.

Multiple choice biology human body respiration in humans mechanism of respiration in animals human lungs

Choose the correct answer from the alternatives given.
The lung is enclosed in a double layered membrane called

  1. pericardium

  2. pleura

  3. periosteum

  4. perichondrium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The pleura refers to the double-layered membrane that covers the lungs. The space between the two membranes is called the pleural cavity. It is filled with a thin, lubricating liquid called pleural fluid, which acts as a lubricant and allows the pleurae to slide effortlessly against each other by reducing friction during respiratory movements. So, the correct option is 'pleura'.

Multiple choice

lungs : breathe :: brain :

  1. speak

  2. head

  3. think

  4. digest
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This is a body part-function analogy: lungs are for breathing, and the brain is for thinking.

Multiple choice zoology not for breathing not for drinking air pollution and its control air pollution - effects and control environmental issues

Air entering lungs is $(1)$ Warmed $(2)$ Filtered $(3)$ Deprived of some oxygem $(4)$ Enriched with $CO _2$. What is true?

  1. $1, 2, 3$ and $4$
  2. $1$ and $2$
  3. $2$ and $4$
  4. $2$ and $3$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

As air enters the lungs, it is warmed by the nasal passages and filtered by cilia and mucus. It is not deprived of oxygen or enriched with CO2; rather, it is the process of gas exchange in the alveoli that performs those functions.