Biology

Respiration and Gas Exchange

989 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 zoology respiratory system phases in respiration human respiratory system parts of respiration

Which of the following statement(s) is (are) true about respiration?
(i) During inhalation, ribs move inward and diaphragm is raised.
(ii) In the alveoli, exchange of gases takes place i.e., oxygen from alveolar air diffuses into blood and carbon dioxide from blood into alveolar air.
(iii) Haemoglobin has greater affinity for carbon dioxide than oxygen.
(iv) Alveoli increase surface area for exchange of gases.

  1. (i) and (iv)

  2. (ii) and (iii)

  3. (i) and (iii)

  4. (ii) and (iv)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

During inhalation, diaphragm contraction occurs which induces the lower ribs to move upward and forward, which also increases thoracic volume. The ribs move outward because the central tendon of the diaphragm (at the crown of the dome) pushes down onto the liver and stomach, which act like a fulcrum. Oxygen enters into the alveoli. Alveoli, is the site for gaseous exchange and they increase the surface area for facilitating the process. 
Carbon monoxide has 210 times greater affinity for haemoglobin than oxygen. Thus, the correct answer is option D.

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

The inspiratory reserve volume + tidal volume + expiratory reserve volume is the same as

  1. inspiratory capacity + expiratory reserve volume

  2. total lung capacity - functional residual capacity

  3. inspiratory capacity + functional residual capacity

  4. inspiratory capacity + residual volume.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Inspiratory reserve volume (IRV) + tidal volume (TV) + expiratory reserve volume (ERV) represents vital capacity (VC). Now, inspiratory capacity is the total volume of air that can be inhaled after a normal expiration. It includes tidal volume and inspiratory reserve volume i.e., IC = TV + IRV. Thus, option (a) is correct which says that vital capacity/.e., IRV + TV + ERV = IC + ERV.

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

Abdominal breathing refers to

  1. Normal breathing

  2. Slow breathing

  3. Fast breathing

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

Diaphragmatic or abdominal breathing is the normal pattern of breathing at rest: the abdomen protrudes as the diaphragm is lowered. It is done by contracting the diaphragm, a muscle located horizontally between the chest cavity and stomach cavity. Air enters the lungs and the belly expands during this type of breathing.This deep breathing is marked by expansion of the abdomen rather than the chest when breathing.

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

Which one of the following statements is not correct?

  1. Pyruvate can be converted into ethanol and carbon dioxide by yeast.

  2. Fermentation is a form of aerobic respiration.

  3. Haemoglobin has greater affinity for carbon dioxide than oxygen.

  4. Alveoli increase the surface area for the exchange of gases.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In fermentation, the carbohydrate gets broken down, but instead of making pyruvate, the final product is a different molecule depending on the type of fermentation. Fermentation is most often triggered by a lack of sufficient amounts of oxygen to continue running the aerobic respiration chain. Humans undergo lactic acid fermentation. Instead of pyruvate, lactic acid is created instead. Other organisms can undergo alcoholic fermentation where the end product is neither pyruvate nor lactic acid. The organism makes ethyl alcohol as an end product. 

Therefore, the correct answer is option B.

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

If a respiratory surface dries out, gas exchange will 

  1. Increase

  2. Decrease

  3. Stop

  4. Not be affected
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The respiratory surface needs moisture for maximum efficiency. Oxygen from the air dissolves in the water on the surface momentarily and this allows the oxygen more time to cross the alveolar membrane. If the surface dries out, gas exchange will happen at a very reduced rate since fast-moving gaseous oxygen molecules do not efficiently cross the alveolar membrane. The reduced gas exchange is mostly likely not enough to support blood oxygenation for vital functions. 

Therefore, the correct answer is option B.

Multiple choice botany movement in and out of the cell diffusion transport in vascular plants types of transport

In which part of the plant, the rate of respiration is higher?

  1. Root and stem tip

  2. Buds

  3. Germinating seeds

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

The highest rate of respiration are found in the actively growing root and stem tips, cambium and embryos of germinating seeds and lowest rates in dormant seeds or spores. As, the growing tips are generally rich in meristematic tissues the rate of respiration is also high.

Multiple choice botany movement in and out of the cell diffusion transport in vascular plants types of transport

Which of the following features does all gas exchange have in common?

  1. They are enclosed within ribs.

  2. They are maintained at constant temperature.

  3. The exchange surfaces are moist.

  4. They are exposed to air.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Out of all the options given the third option is the correct one.
Exchange of gases is a feature that is common in all living things. Irrespective of the genera of living organisms,  all organs that exchange gases are characterized by features such as- thin, moist, large surface area and a large capillary network.

Multiple choice zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

Panting after vigorous exercise is due to

  1. Oxygen debt

  2. Continuity of deep breathing even after exercise

  3. Continuity of mouth breathing started during exercise

  4. Requirement of rapid dissipation of energy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • During a vigorous physical exercise, lactic acid and carbon dioxide are formed in the muscles of the body.
  • The production of lactic acid can be prevented by the flow of required oxygen to the muscles thus, our body uses more oxygen than replenished.
  • Therefore, after a vigorous exercise people pant due to to decrease in the oxygen level in the body.
  • So, the correct answer is 'Oxygen debt'.
Multiple choice evs roots and leaves leaves root, stem, and leaves basics of roots and stem plant adaptation and modification

Which part of the leaf is useful for exchanging gases between the plant and the atmosphere?

  1. Midrib

  2. Stomata

  3. Veins

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

A)The midrib is the large strong the central vein in the middle of the leaf.
B)Stomata are the part of leaf present on the epidermis and help in the gaseous change.
C)Veins are the vascular tissue of leaf located at the mesophyll part.
D)The petiole is the part of a leaf that joins the lamina to the base.
So the correct option is 'Stomata'

Multiple choice biology biology : an introduction introduction to organization of life signs of life what is living?

The process of taking in and giving out of the air is known as 

  1. Breathing

  2. Inhaling

  3. Exhaling

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Breathing is process of taking in and giving out of the air for exchange of gases between the internal of body and the external environment. The taking in of air is called as inhalation and giving out of air is called exhalation. It is an important part of respiration and can be done by various organs like nose, skin, gills.
Hence the correct option is A "breathing".
Multiple choice biology breathing and respiration regulation of breathing human respiratory system contro and disorders of respiration

The structure which prevents the entry of food into respiratory tract is

  1. Pharynx

  2. Larynx

  3. Glottis

  4. Epiglottis
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The epiglottis is a flap-like structure made of elastic cartilage tissue covered with a mucous membrane, attached to the entrance of the larynx. The main function of the epiglottis is to close off the windpipe during eating which prevents the entry of the food into the respiratory tract so that food is not accidentally inhaled. Hence option D is correct.