QS Study

During respiration whole energy contained in the respiratory substrates is not released in a single step or released free into the cell, if not the cell would be burnt. The efficiency of respiration is the proportion of total free energy captured in ATP during complete oxidation of a mole of the respiratory substrate.

Conditions that decrease Respiratory Efficiency –

Constriction of the Bronchi (Bronchial Asthma):

One of the problems associated with bronchial asthma is the spasm of the smooth muscle in the wall of the bronchioles. This particularly reduces the diameter of the bronchioles during expiration, usually causing the asthmatic patient to experience great difficulty in expiring, although inspiration is accomplished normally. The lungs consequently become greatly distended and the thoracic cage becomes permanently enlarged, forming the so-called barrel chest. In addition, the air flow through the bronchioles is further impeded by the presence of excess mucus, which the patient is unable to clear because an effective cough cannot be produced.

Loss of Lung Elasticity

Many diseases of the lungs, such as emphysema and pulmonary fibrosis, destroy the elasticity of the lungs, and thus the lungs are unable to recoil adequately, causing incomplete expiration. The respiratory muscles in these patients have to assist in expiration, which no longer is a passive phenomenon.

Loss of Lung Dispensability

Diseases such as silicosis, asbestosis, cancer, and pneumonia interfere with the process of expanding the lung in inspiration. A decrease in the compliance of the lungs and the chest wall then occurs, and a greater effort has to be undertaken by the aspiratory muscles to inflate the lungs.

Related Study: