Tag: zoology

Questions Related to zoology

The exchange of gases between which of the following is called external respiration?

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

  1. Lung alveoli and blood capillaries

  2. Lung alveoli and bronchi

  3. The buccal cavity and the external atmosphere

  4. Lung alveoli and pulmonary artery

Show answer
Correct Option: A
Explanation:

When the gaseous exchange occurs due to a difference in the partial pressure of gases between alveoli of lungs and capillaries it is termed as an external exchange as it involves air that ix either inhaled or exhaled from the environment outside the body while when the exchange occurs between capillaries and tissue it is known as the internal exchange.

So the correct option is 'Lung alveoli and blood capillaries'.

Which of the following is the correct path of oxygen in humans during inhalation?

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

  1. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Pharynx $\rightarrow$ Trachea $\rightarrow$ Bronchi $\rightarrow$ Bronchiole $\rightarrow$ Alveoli

  2. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Trachea $\rightarrow$ Pharynx $\rightarrow$ Bronchi $\rightarrow$ Bronchiole $\rightarrow$ Alveoli

  3. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Pharynx $\rightarrow$ Trachea $\rightarrow$ Alveoli $\rightarrow$ Bronchi $\rightarrow$ Bronchiole

  4. Nostrils $\rightarrow$ Nasal Cavity $\rightarrow$ Pharynx $\rightarrow$ Bronchi $\rightarrow$ Trachea $\rightarrow$ Bronchioles $\rightarrow$ Alveoli

Show answer
Correct Option: A
Explanation:
The correct path of oxygen transfer is nostrils - external structures, nasal passage or the nasal cavity then into the pharynx followed by trachea and bronchii to smaller branches called the bronchioles and lastly the alveoli from where it is exchanged into the blood stream with the help of capillaries surrounding the alveoli.
So, the correct answer is Nostrils →→ Nasal Cavity →→ Pharynx →→ Trachea →→ Bronchi →→ Bronchiole →→ Alveoli

Which of the following is true for $CO _2$ concentration?

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

  1. More in alveolar air than in expired

  2. More in expired air than in alveolar air

  3. More in inspired air than in alveolar air

  4. More in inspired air than in expired air

Show answer
Correct Option: A
Explanation:

In the alveoli, the oxygen is continuously absorbed by the blood and CO$ _{2}$ is continuously added by the blood. So, the alveolar air has more CO$ _{2}$ concentration than the expired air.

Hence, the correct answer is 'More in alveolar air than in expired air'

The gas which we breath out precipitates ______ into milky white.

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

  1. Sodium Chloride solution

  2. Calcium Carbonate solution

  3. Potassium Permanganate solution

  4. Potassium Bicarbonate solution

Show answer
Correct Option: B
Explanation:

The gas which we exhale or breath out is carbon-dioxide. 

When this gas passes through calcium carbonate solution there occurs precipitation reaction between the solution, as a result, the color of the solution turns to milky white.
When CO$ _2$ is passed through lime water which is a diluted solution of Ca(OH)_2, it turns milky due to the formation of calcium carbonate $CaCO _3$.

So the option B is correct.

Inspiration occurs when

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

  1. Pressure inside lungs is lower than atmospheric pressure

  2. Pressure inside lungs is higher than atmospheric pressure

  3. Pressure inside lungs is same as atmospheric pressure

  4. Pressure has no effect

Show answer
Correct Option: A
Explanation:

Air can be forced to move from one place to another by creating a pressure gradient. In the human body, the contraction of the diaphragm allows it to move down to abdomen cavity slightly. This increases the area in the thoracic cavity and the lungs expand. The intercostal muscles between the ribs also contract and allow the rib bones o come upwards and outward. Due to this, volume in the lungs increases and the pressure decreases. The pressure in the lungs is less than that of atmospheric pressure, so the air is drawn in and inspiration occurs.

Hence, the correct answer is 'Pressure inside lungs is lower than atmospheric pressure'

Lungs become empty after forceful expiration.

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

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

Lungs are never empty even after forceful expiration. There is always a certain amount of air present in the lungs which is known as residual volume which amounts to 1500 ml. 

Thus, the correct answer is option B. 

Maximum contraction of diaphragm causes maximum expiration.

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

  1. True

  2. False

Show answer
Correct Option: B
Explanation:

When the intercostal muscles and the diaphragm contract they increase the size of the thoracic cavity, causing negative pressure in the lungs, causing inspiration.
So, the correct answer is option B.

The width of the chest during inspiration :

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

  1. Decreases

  2. Does not change

  3. Increases

  4. None of these

Show answer
Correct Option: B
Explanation:

  • When you breathe in, or inhale, your diaphragm contract and move downward. This increases the space in the chest cavity into which lungs expand.
  • The intercostal muscles between ribs also help enlarge the chest cavity.
So, the correct option is 'Does not change'.

Which respiratory associated muscles would be contracted if you blow up a balloon?

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

  1. Diaphragm contracts and internal intercostal muscles would relax

  2. External intercostal muscle contract and phrenic muscles would contract

  3. Internal intercostal and abdominal muscle would contract

  4. Internal intercostal muscles are external intercostal muscles would contract

Show answer
Correct Option: B
Explanation:

Intercostal and abdominal muscle would contract if we blow up a balloon. When this occurs, you are interrupting the natural rhythm of breathing. The inhalation process is blowing up a balloon. As you this movement is facilitated by the contraction of the external intercostal muscles.

So the correct answer is' Internal intercostal and abdominal muscle would contract'.

Volume of thoracic chamber increases in the anteroposterior and dorsoventral axis in the human by?

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

  1. Contraction of diaphragm and external intercostal muscles

  2. Relaxation of diaphragm and external intercostal muscles

  3. Relaxation of diaphragm and abdominal muscles

  4. None of these

Show answer
Correct Option: A
Explanation:

Volume of thoracic chamber increases in anteroposterior and dorso-ventral axis in human by contraction of diaphragm and external intercostal muscles.