Biology

Respiration and Gas Transport

606 Questions

Respiration and gas transport deal with the physiological mechanisms of breathing, including the role of hemoglobin in oxygen transport and the removal of carbon dioxide from the blood. Questions cover both aerobic and anaerobic processes, along with related phenomena like altitude sickness. This human biology topic is a staple in the science sections of competitive tests.

Oxygen and hemoglobin transportAnaerobic respiration effectsCarbon dioxide removalAltitude sickness causesBreathing rate regulation

Respiration and Gas Transport Questions

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

The air we breathe out contains more

  1. Oxygen

  2. Carbon dioxide

  3. Water

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

  • The respiratory tract carries air from the mouth and nose to the lungs.
  • In the lungs, the gases oxygen and carbon dioxide are exchanged between the alveoli and the capillaries. 
  • Exhaled air contains less oxygen and more carbon dioxide, Hence, The air we breathe out contains more carbon dioxide.
So, the correct answer is 'carbon dioxide'.

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

Carbon dioxide in the expired air is more than that in inspired air because

  1. It is absorbed at the alveolar surface

  2. It is released at the alveolar surface

  3. Both A and B

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Component                        Inspired air         Expired air
  $CO _2$                                    0.04%                   4%
Because carbon dioxide is released at the alveolar surface during the gaseous exchange between blood and alveoli.

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

$CO _2$4 is transported mainly as.

  1. Dissolved in blood plasma

  2. As carbonic acid

  3. In carbaminohaemoglobin

  4. As carbaminohaemoglobin and carbonic acid
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

CO2 is transported in the blood primarily as bicarbonate ions, but also as carbaminohaemoglobin (bound to hemoglobin) and dissolved in plasma. Option D covers the main transport mechanisms.

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

People migrated from planes to hills six months back.

  1. Possess more RBCs with haemoglobin of low $O _2$ binding affinity
  2. Possess same RBCs with haemoglobin of high $O _2$ binding affinity

  3. Lose physical fitness to play games like football

  4. Suffer from altitude sickness with nausea and fatigue
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

At high altitudes, the partial pressure of oxygen is lower. To compensate for the reduced oxygen availability, the body increases the production of red blood cells and alters hemoglobin affinity to facilitate better oxygen delivery to tissues.

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

People living at sea level have around 5 million $RBCs/mm^3$ of blood whereas those living at an altitude of 5400 m have around 8 million. This is due to

  1. There is more UV radiation which enhances RBCs production

  2. People eat more nutritive food which helps in formation of more RBCs

  3. People get pollution free air to breathe with more oxygen becoming available
  4. Atmospheric $O _2$ level is less so that more RBCs are needed to absorb the required amount of $O _2$ to survive.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

At high altitudes, the partial pressure of oxygen is lower. The body compensates for this hypoxia by increasing the production of red blood cells (erythropoiesis) to increase the oxygen-carrying capacity of the blood.

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

Breathing rate increase during physical exercise because

  1. Cells require extra oxygen

  2. Cells require extra energy

  3. Cells require carbon dioxide

  4. Both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Breathing rate is defined as the no. of times a person breathes in a minute. Breathing rate increase during physical exercise because at that time body demands a high amount of oxygen in the blood for metabolism. The body requires extra energy to carry out muscular activity.
So the correct answer is 'Both A and B'.
Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

Which component of air is exhaled by the body?

  1. Nitrogen

  2. Oxygen

  3. Carbon dioxide

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

Carbon dioxide is a waste product of the body. It is majorly exhaled out by the body so that it will reduce the competition to gets bind to the haemoglobin with oxygen. It is saturated with water vapours.

So the correct answer is 'Carbon dioxide'.

Multiple choice evs respiration in organism human respiration the mechanism of breathing breathing and its movements

Which component from the inhaled air is used by the body?

  1. Carbon dioxide

  2. Nitrogen

  3. Oxygen

  4. Hydrogen
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Inhalation (breath in) and exhalation (breath out) is a part of respiration. During inhalation oxygen is inhaled with air as major component which plays key role in metabolism.
So the correct answer is 'Oxygen'.
Multiple choice biology respiration and energy transfer respiratory quotient-basic respiration-plants respiratory quotient

Respiratory quotient is expressed as which of the following equations?

  1. $O _2/CO _2$
  2. $CO _2/O _2$
  3. $O _2/H _2O$
  4. $CO _2 - O _2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During aerobic respiration, $O _2$ is consumed and $CO _2$ is released. The ratio of the volume of $CO _2$ evolved to the volume of $O _2$ consumed in respiration is called the respiratory quotient (R.Q) or respiratory ratio.  Thus the following expression is used to calculate the value of R.Q.
RQ= volume of $CO _2$ evolved/ volume of $O _2$ consumed.

Multiple choice biology blood circulatory system of human blood clotting platelets and their function defence against infectious disease

$1$ li. of oxygenated blood can deliver how much amount of $O _2$ to the tissue under normal conditions.

  1. $4$ ml
  2. $50$ ml
  3. $20$ ml
  4. $159$ ml
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Under normal physiological conditions, every 100 ml of oxygenated blood delivers approximately 5 ml of oxygen to the tissues. Therefore, 1 liter (1000 ml) of oxygenated blood delivers about 50 ml of oxygen.

Multiple choice biology biogeochemical cycles carbon cycling mineral coal carbon cycle

Affinity of hemoglobin for CO is two hundred times more considerable than

  1. $O _{2}$
  2. $CO _{2}$

  3. Sox

  4. Nox
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Carbon monoxide (CO) binds to hemoglobin with an affinity approximately 200 to 250 times greater than that of oxygen (O2), which is why CO poisoning is so dangerous.