Biology

Respiration and Gas Transport

647 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 water and air and their importance natural resources- air, water and land air around us air chemistry introduction to natural resources land

Which of the following is not a sink for CO?

  1. Haemoglobin

  2. Microorganims present in the soil

  3. Oceans

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation


* Incomplete combustion of fossil fuels liberate CO into air. 80% of CO is released from automobiles.


* Permissible level of CO in air is 9 ppm. It reduces $O _2$ supply in human by forming a stable carboxyhaemoglobin.

$2C+O _2\rightarrow 2CO$
$2CH _4+3O _2\rightarrow 2CO+4H _2O$

* CO interacts with oxyhaemoglobin ($O _2Hb$) and forms carboxyhaemoglobin (CO-Hb) as :

$O _2Hb+CO\rightarrow COHb+O _2$

* CO has high affinity for haemoglobin than that of oxygen.

Therefore, option A is correct.

Multiple choice evs respiration in living organisms respiration in human beings respiration and associated structures respiration in humans mechanism of respiration in animals human lungs respiratory organs in humans

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

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

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

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

  4. (iv), (vi), (ii), (v), (i), (iii)
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

While respiration atmospheric air is drawn in a carbon dioxide is released out, diffusion of gases takes place in the alveolar tissue which is then carried by blood, then diffusion of gases take place between blood and tissues, oxygen is utilized by cells for catabolic reactions, and the resultant carbon dioxide is released from the body.

So, the correct option is '(iii), (vi), (ii), (v), (i), (iv)'.

Multiple choice evs respiration in living organisms respiration in human beings respiration and associated structures respiration in humans mechanism of respiration in animals human lungs respiratory organs in humans

The exhaled air mainly contains

  1. Oxygen

  2. Carbon dioxide

  3. Nitrogen

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

Exhalation is a process to breath out.carbon dioxide is a waste product in the body that release out during exhalation, it is also saturated with water vapor.

So the correct answer is "carbon dioxide".

Multiple choice evs respiration in living organisms respiration in human beings respiration and associated structures respiration in humans mechanism of respiration in animals human lungs respiratory organs in humans

Increase in $CO _2$ concentration shall cause.

  1. Slower and shallower breathing

  2. Slower and deeper breathing

  3. Faster and deeper breathing

  4. No effect on breathing
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Increased CO2 concentration in the blood (hypercapnia) is detected by chemoreceptors, which signal the respiratory center in the brain to increase the rate and depth of breathing to expel excess CO2.

Multiple choice evs circulation of blood circulatory system and organs basics of blood and heart transportation in living organisms

Why it is necessary to separate oxygenated and deoxygenated blood in mammals and birds?

  1. To stop mixing of oxygenated and deoxygenated blood

  2. To maintain body temperature

  3. To suffice higher energy need

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The heart of the higher organism is well equipped with the vascular system. the arteries carry the oxygenated blood while the veins carry the deoxygenated blood. This prevents the mixing of oxygenated and deoxygenated blood.

So, the correct answer is option A.

Multiple choice chemistry non-metals carbon dioxide - an oxide of carbon component of air - carbon dioxide oxides of non metal

Dissolved air contains a higher percentage of oxygen than ordinary air.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dissolved air has a higher percentage of oxygen as compared to ordinary air. Air dissolved in water contains 36% oxygen as compared to 21% in air. This is because oxygen in the air has a higher solubility than other elements in air and also there is hydrogen bonding between water and oxygen that increases its solubility.

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

Mountain sickness results due to

  1. Anaemic hypoxia

  2. Arterial hypoxia

  3. Lack ofsufficient RBCs

  4. Lack ofsufficient WBCs
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Arterial hypoxia (also known as hypoxiation or anoxemia) is a condition in which the body or a region of the body is deprived of adequate oxygen supply. Hypoxia may be classified as either generalized, affecting the whole body, or local, affecting a region of the body. Generalized hypoxia occurs in healthy people when they ascend to high altitude, where it causes altitude sickness or mountain sickness leading to potentially fatal complications: high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE). Thus, option B is correct.

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

Asphyxia occurs due to.

  1. Rise in level of $CO _2$
  2. Fall in level of $CO _2$
  3. Rise of $O _2$ level
  4. Fall in $O _2$ level
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Asphyxia is a condition of severely deficient supply of oxygen to the body that arises from being unable to breathe normally, often caused by an accumulation of carbon dioxide in the blood.

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

The mountaineers carry oxygen with them because.

  1. At an altitude of more than $5$km there is no air

  2. The amount of air available to a person is less than that available on the ground

  3. The temperature of air is higher than that on the ground

  4. The pressure of air is higher than that on the ground
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The atmospheric pressure goes on decreasing as we go up above the sea level, and the amount of oxygen also decreases at higher altitude. 

So the correct option is 'The amount of air available to a person is less than that available on the ground.'

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

Ravi, who lived at sea level, had around 5 million RBC per cubic millimeter of his blood. Later when he lived at an altitude of 18,000 ft, showed around 8 million RBC per cubic millimeter of blood. This is an adaptation because

  1. At high altitude, he ate more nutritive food.

  2. He had pollution free air to balance breathe.
  3. At high altitude O$ _2$ level is less, hence, more RBCs were required to absorb enough oxygen.

  4. At high altitude, there is more UV radiation which enhances RBCs production.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

At sea level, our blood is 98% saturated with oxygen and this decreases to 89% at 3000 metres and reaches as low as 40% on the summit of Everest. Red blood cell production increases, resulting in an increased haemoglobin concentration, which is required to pick up oxygen and transport it around the body. This mechanism enables the body to continue to deliver enough oxygen to each cell, despite the lower oxygen levels. 

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

Ascent of high mountains may cause altitude sickness in men. Prime cause of this is

  1. Excess of O$ _2$ in blood

  2. Decreased efficiency of haemoglobin

  3. Decreased partial pressure of oxygen

  4. Decreased proportion of oxygen in air
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

 Altitude sickness (also known as mountain sickness), is caused by gaining altitude too rapidly, which does not allow the body enough time to adjust to reduced oxygen and changes in air pressure, and causes hypobaric hypoxia (a lack of oxygen reaching the tissues of the body).

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

Read the statements carefully and choose the option representing true statements.
(a) $pO _2$ in the atmospheric air does not change with altiude
(b) Most people who live at high altitude develop polycythemia due to hypoxia
(c) Excess inflation to the lungs is prevented by Hering-Breuer's reflex
(d) While transporting $CO _2$ in blood, blood does not become acidic due to presence of blood buffers.

  1. (a) & (c) only

  2. (b) & (c) only

  3. (a), (b) & (c) only

  4. (b), (c) & (d) only
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$pO _2$ of atmospheric air decreases with increasing altitude.

Most people living at high altitude develop polycythemia due to hypoxia as oxygen levels are low.
Hering Breuer's reflex prevent excessive inflation of lungs .
Blood has an efficient buffer system which resists the change in pH even after dissolution of carbon dioxide.
So the correct answer is '(b), (c) & (d) only '.

Multiple choice biology the respiratory system factors affecting breathing exchange of gases transport of respiratory gases

When the blood contains a high percentage of $CO _2$ and a very low percentage of $O _2$ the breathing stops and the person becomes unconscious. This condition is known as.

  1. Suffocation

  2. Asphyxia

  3. Emphysema

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

Asphyxia is the extreme condition caused by lack of oxygen and excess of carbon dioxide in the blood, produced by interference with respiration or insufficient oxygen in the air; suffocation. Asphyxia is caused by an injury or obstruction of airway passages. So, the correct answer is option B.