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 biology respiration and energy transfer respiratory quotient-basic respiration-plants respiratory quotient

The respiratory quotient during cellular respiration would depend upon

  1. Amount of $CO _{2}$ released
  2. Amount of $O _{2}$ utilized

  3. The nature of enzyme in invoked

  4. Nature of substrate

  5. Both (a) and (b)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The respiratory quotient (R.Q) is the ration of the volume of the CO$ _{2}$ released to the volume of the O$ _{2}$ utilized by a substrate during the process of respiration. It solely depends on the nature of the substrate. The R.Q. reflect the nature of the substrate, for example, R.Q. 1 indicated that glucose is the respiratory substrate.

Hence, the correct answer is 'Nature of substrate'.

Multiple choice zoology respiratory system phases in respiration human respiratory system parts of respiration

The rate at which oxygen moves from the alveoli of our lungs into our blood

  1. Depends on the difference in oxygen concentration between the alveoli and the blood.

  2. Depends on the color of the alveoli.

  3. Depends on the availability of energy to transport gases across the membrane.

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

The rate at which oxygen moves from the alveoli of our lungs into our blood depends on the difference in oxygen concentration between the alveoli and the blood. More is the oxygen absorbed by our lungs, more is it utilized by body muscles.

Multiple choice zoology respiratory system phases in respiration human respiratory system parts of respiration

Utilization of $O _2$ by the cells to derive energy from nutrients for performing various activities and resultant release of $CO _2$ as by-produced is called

  1. Breathing

  2. Cellular respiration

  3. Pulmonary ventilation

  4. Fermentation
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation
 Name of the process  By-product
 Breathing   CO2
 Cellular respiration   CO2 + H2O+ 38 ATP
 Pulmonary ventilation  Commonly known as breathing, so as breathing the by-product is  CO2
 Fermentation(takes place in anaerobic condition) Ethanol + CO2 (alcohol fermentation)Lactate (lactic acid fermentation).

So, the correct answer is 'Breathing', 'Cellular respiration' and 'Pulmonary ventilation'.

Multiple choice zoology respiratory system phases in respiration human respiratory system parts of respiration

Amount of $O _2$ normally carried by 100 ml of pure blood, is

  1. 40 ml

  2. 10 ml

  3. 20 ml

  4. 30 ml
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Oxygen is carried in the blood either in dissolved form or in association with  hemoglobin.
However, to calculate the concentration of oxygen transported in the blood, one need to understand the amount of oxygen carried by each gram of hemoglobin. In a saturated condition, one gram of hemoglobin  carries 1.34 ml of oxygen. Normally 100 ml of blood has  around 15 gm of hemoglobin in it.
Thus, the amount of oxygen carried in 100 ml of pure blood can be calculated as 15 * 1.34 ml = 20 ml
Multiple choice zoology respiratory system phases in respiration human respiratory system parts of respiration

When we breathe in air, nitrogen also goes inside along with oxygen. What is the fate of this nitrogen?

  1. It moves along with oxygen into the cells.
  2. It comes out with the $CO _{2}$ during exhalation.

  3. It is absorbed only by the nasal cells.

  4. Nitrogen concentration is already more in the cells so it is not at all absorbed.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Breathing is an act of ventilating a respiratory surface with air. Breathing is usually accomplished through muscular movements that can be divided into inspiration (intake of air ) and expiration (outflow of air). The composition of inhaled air is 20.94 % oxygen, 0.04 % carbon dioxide, 79.02 % nitrogen and trace gases. The composition of exhaled air is 16.49 % oxygen, 4.49 % carbon dioxide, 79.02 % nitrogen and other trace gases. The nitrogen is an inert gas, during breathing, there is no change in nitrogen percentage in inhaled as compared to exhaled air.

Multiple choice zoology respiratory system phases in respiration human respiratory system parts of respiration

Diffusion is insufficient to meet $...............$ requirements of multicellular organisms.

  1. Carbon dioxide

  2. Oxygen

  3. Nitrogen

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

Diffusion is insufficient to meet the oxygen requirement of multicellular organisms like human because all the cells are not direct contact in environment and diffusion is a slow process. Diffusion is too slow to cover the distance between the gas exchange surface and the sites where the oxygen is required. That is why we need a gas transport system - the bloodstream. It would be difficult to allow passive diffusion to transfer oxygen because there would need to be gradients across each and every cell. In the end, it would be too slow and impractical for any multicellular organism to use.

Multiple choice economics environment pollution strategies to control environmental pollution strategies to control pollution strategies to control environmental pollution and green chemistry

Carbon monoxide emitted by automobiles prevents transport of oxygen in body due to:

  1. its combination with oxygen to form carbon dioxide

  2. break down of haemoglobin

  3. preventing haemoglobin to form oxyhaemoglobin

  4. formation of free radicals in the blood
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Carbon dioxide and carbon monoxide gases are emitted during the combustion of various fuels. Carbon monoxide is poisonous, whereas carbon-dioxide is non-toxic in nature. Carbon monoxide is poisonous because it is capable of forming a complex with hemoglobin (carboxyhaemoglobin), which is more stable than the oxygen-haemoglobin complex. The concentration range of 3–4% of  carboxyhaemoglobin decreases the oxygen-carrying capacity of blood. This results in headaches, weak eyesight, nervousness, and cardiovascular disorders. A more increased concentration may even lead to death.

Carbon monoxide when binds to hemoglobin forms a stable compound - carboxyhaemoglobin. Since, oxygen of carbon monoxide binds more readily to hemoglobin than do Oxygen of carbon dioxide, therefore carbon monoxide prevents carbon dioxide from binding to Hb, which means diffusion or exchange of gases won't take place at alveolar site. So, carbon monoxide is more harmful because it prevents oxygen from entering the body.

Multiple choice bio-chemistry carbohydrate metabolism metabolism enzymes metabolism, cell respiration, and photosynthesis

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)  Released 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), (vii), (ii), (v), (i), (iv)

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

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

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

In the given question, the correct sequence of steps of respiration is:
(iii) Pulmonary ventilation by which atmospheric air is drawn in and CO2 is released out.
(vi) Diffusion of gases (O2 and CO2) across alveolar tissues.
(ii)   Transport of gases by the blood.
(v)   Diffusion of O2 and CO2 between blood and tissues.
(i)    The utilisation of O2 by the cells for catabolic reactions.
(iv)  Released resultant CO2.


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

Multiple choice biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

Haemoglobin is composed of four subunits. When one subunit binds to oxygen, it increases the chances that the other three subunits will also bind to oxygen. What is this type of activity called?

  1. Inhibition

  2. Cooperativity

  3. Enzyme substrate complex

  4. Catalysis

  5. Activation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. When the binding of chemical shuts off the enzymatic activity, the process is called inhibition.
B. When binding of a molecule to the enzyme increase its affinity for more molecules, it is called cooperativity.
C. Binding of the substrate to the active site of enzyme produces a highly reactive short lived complex called Enzyme substrate complex which breaks into chemical products and unchanged enzyme.
D. Catalysis is the increase in rate of reaction by a catalyst.
E. Activation is the start of reaction by an enzyme.
Hence, the increase in affinity of haemoglobin for oxygen by binding of one oxygen molecule, is cooperativity.
So, the correct answer is 'Cooperativity'.
Multiple choice biology metabolism, cell respiration, and photosynthesis metabolism enzymes carbohydrate metabolism

Cyanide causes irreversible inhibition of cytochrome oxidase. This is because it

  1. Combines with iron.

  2. Destroys tertiary structure.

  3. Attaches to copper.

  4. All the above.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Cyanide inhibits cytochrome oxidase by combining with Iron within the enzyme which results in the prevention of transport of electrons from cytochrome oxidase to oxygen. So, the correct answer is A.
Multiple choice zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

During heavy exercise, we get cramps in the legs due to the accumulation of

  1. Carbon dioxide

  2. Lactic acid

  3. Alcohol

  4. Water
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • During heavy exercise, the demand for energy is high but the supply of oxygen to produce energy is limited. Therefore, anaerobic respiration takes places in the muscles cells to fulfil the demand for energy. This anaerobic breakdown of glucose leads to the formation of lactic acid in muscles. The accumulation of lactic acid in muscles leads to muscle cramps.
  • HenceDuring heavy exercise, we get cramps in the legs due to the accumulation of Lactic acid.
  • So, the correct answer is 'Lactic acid'.
Multiple choice zoology bio-geo chemical cycles in nature nitrogen cycle biogeochemical cycles - gaseous nutrient cycles

In excess, $C{O} _{2}$

  1. Accelerates growth

  2. Does not influence growth

  3. Inhibits growth

  4. Slows down growth
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Atmospheric carbon dioxide is used by plants to produced food. Due to industrialization, large amount of carbon dioxide is released in the atmosphere. This CO$ _2$ provides nutrient source to certain plants. However, excess amount of CO$ _2$ inhibits growth in plants. It inhibits nitrate assimilation in certain plants. It basically inhibits absorption of nitrogen.

Thus, the correct answer is option C.

Multiple choice biology properties of natural resources the concept of bernoulli's principle variations in atmospheric pressure air exerts pressure

Mountaineers carry oxygen cylinders with them because:

  1. oxygen supports combustion

  2. air becomes thinner as we go higher

  3. air is dense but lacks oxygen in mountains

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

As we go higher and higher the pressure and oxygen decreases, so as due to less oxygen content mountaineers carry oxygen cylinders with them.

Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

Select the correct option:

Mercury (Hg) is generally used in anaerobic respiration experiments because it does not react with ___________.

  1. ${O} _{2}$
  2. ${CO} _{2}$
  3. ${H} _{2}O$
  4. $air$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Mercury is very reactive towards oxygen. It reacts with the oxygen in the air and also reacts with dilute acids containing oxygen. However, mercury is comparatively non-reactive in water. This is why it is used in anaerobic respiration experiments.
So, the correct answer is '$H _2$O'