Question

Which energy is consumed in breathing?
(a)Mechanical
(b)Chemical
(c)Bioelectricity
(d)Physical energy

Answer 1

Hint: The process required in breathing involves the movement of the diaphragm, intercostal muscles, and abdominal muscles in order to change the volume of the thoracic cavity which will result in a change in the pulmonary volume which is essential for inhalation and exhalation.

Complete Answer:
The energy consumed in the process of breathing is chemical energy which is released as a result of metabolic reactions taking place in the body. These metabolic reactions are responsible for breaking down the complex organic food into simple inorganic molecules and trap the energy released during the breaking of these C-C bonds in the form of ATP (Adenosine triphosphate). ATP is known as the energy currency of the cell and is responsible for storing energy temporarily in its bonds until it is required later. All the reactions that result in the release of ATP come under the process of cellular respiration.

Additional information:
Let us look at the process of breathing in detail:
The process of breathing takes place by creating a pressure gradient between the atmospheric pressure and the pressure inside the lungs (intrapulmonary pressure).
Inhalation: In this stage, atmospheric air is drawn into the lungs. Inhalation takes place when the intrapulmonary pressure is less than atmospheric pressure, thus causing air to move inside the lungs. This decrease in the pulmonary pressure is achieved by contracting the diaphragm, intercostal muscles which result in increasing the volume of the thoracic cavity and a decrease in the pressure.
Exhalation: In this stage, the alveolar air is released back to the outside. Exhalation takes place when the intrapulmonary pressure is higher than atmospheric pressure and thus causing air to move outside the lungs. This increase in the pressure is achieved by relaxing the diaphragm and intercostal muscles which result in a decrease in the volume of the thoracic cavity, thus increasing the pressure inside the lungs.

So, the correct option is ‘Chemical’.

Note:
-The intercostal muscles are muscle groups present near the ribs which make up the chest wall as well as move the chest wall for the purpose of breathing.
-Intercostal muscles are of the following 3 types known as the ‘Innermost intercostal muscles’ as they are present inside the ribs, the ‘Internal intercostal muscles’ as they are present in between the ribs, and the ‘External intercostal muscles’ as they are present outside the ribs.
-The diaphragm is a skeletal muscle that is present at the base of the chest cavity. It helps in the process of inhalation and exhalation by contracting and relaxing respectively.