Tag: zoology

Questions Related to zoology

Read the following statements regarding mechanism of respiration and choose the correct option.
$1$. Inspiration occurs only when there is negative pressure in the lungs with respect to atmosphere
$2$. Expiration takes place only when intrapulmonary pressure is lower than atmospheric pressure
$3$. Pressure gradients are generated with the help of diaphragm and intercostal muscles
$4$. Inspiration is initiated by relaxation of diaphragm
$5$. Contraction of diaphragm reduces pulmonary volume and increases intrapulmonary pressure causing expiration.

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. $1, 2$ and $5$ correct

  2. $2$ only correct

  3. $2, 5$ correct

  4. $1, 3$ correct

  5. $1, 4$ correct

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Correct Option: D

With conscious efforts one can.

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. Breathe out air totally without oxygen

  2. Breathe in and out by moving diaphragm alone without moving ribs at all

  3. Breathe out air through eustachian tube by closing both nose and mouth

  4. Empty the lungs completely by breathing out all air out of them

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Correct Option: B

Which of the following is the most appropriate in normal circumstances?

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. During inspiration the intrapulmonary pressure is less than the atmospheric pressure

  2. During expiration the intrapulmonary pressure is less than the atmospheric pressure

  3. During inspiration the intrapulmonary pressure is more than the atmospheric pressure

  4. During expiration the intrapulmonary pressure is equal to atmospheric pressure

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Correct Option: A

Diaphragm is straightened during.

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. Expiration

  2. Inspiration

  3. Interval between expiration and inspiration

  4. Interval between inspiration and expiration

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Correct Option: A

A person breathes in some volume of air by forced inspiration after having a forced expiration. This quantity of air taken in is _______________.

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. Total lung capacity

  2. Tidal volume

  3. Vital capacity

  4. Inspiratory capacity

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Correct Option: A

During inspiration, the pressure of air is maximum in ___________.

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. Trachea

  2. Bronchus

  3. Alveoli

  4. Environment

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Correct Option: A

In negative pressure breathing, inhalation results from:

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. forcing air from the throat down into the lungs

  2. contracting the diaphragm

  3. relaxing the muscles of the rib cage

  4. contracting the abdominal muscles

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Correct Option: B
Explanation:

During the process of inhalation, the lung volume expands as a result of contraction of the diaphragm & intercostal muscles, thoracic cavity expands, due to this increase in volume, the pressure is decreased.

So, the correct option is 'contracting the diaphragm'.

During expiration the diaphragm becomes

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. dome-shaped

  2. oblique

  3. concave

  4. flattened.

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Correct Option: A
Explanation:

When the internal intercostal muscles contract and diaphragm relax, the ribs move .downward and inward and diaphragm becomes convex {dome shaped), thus decreasing the volume of thoracic cavity and increasing the pressure inside as compared to the atmospheric pressure outside. This will cause the air to move out (expiration).

After forceful inspiration, the amount of air that can be breathed out by maximum forced expiration is equal to

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. Inspiratory Reserve Volume (IRV) + Expiratory Reserve Volume (ERV) + Tidal Volume (TV) + Residual Volume (RV)

  2. IRV + RV + ERV

  3. IRV + TV + ERV

  4. TV + RV + ERV

Show answer
Correct Option: C
Explanation:

Vital capacity is the maximum volume of air a person can breathe in after a forced expiration or the maximum volume of air a person can breathe out after a forced inspiration.This equals the inspiratory reserve volume (IRV) + expiratory reserve volume (ERV) + tidal volume (TV). Its value is 3400 mL - 4800 mL..

Read the following four statements (i) - (iv) with certain mistakes in two of them.
(i) A water breather expends much more energy in ventilating its respiratory surface than an air-breathing one.
(ii)   Lungs become empty after forceful expiration.
(iii) Exchange of gases in the lungs is interrupted during expiration.
(iv) Respiratory movements are controlled by $CO _{2}$ concentration of arterial blood.
Which of the above two statements have mistakes?

zoology respiratory system of human mechanism of respiration respiratory cycle breathing and exchange of gas

  1. (i) and (iv)

  2. (ii) and (iii)

  3. (i)and(ii)

  4. (iii) and (iv)

Show answer
Correct Option: B
Explanation:

 Corrected statements:

(ii) Lungs do not become empty after a forceful expiration.

(iii) The exchange of gases in the lungs is not interrupted during expiration.

So, the correct answer is '(ii) and (iii)'.