What step is not involved in respiration in human beings?

The diffusion of carbon dioxide and oxygen between tissues and blood is not a step in human respiration.

Human respiration is a complex physiological process that involves several interconnected steps, including:

The process by which atmospheric air is drawn into the lungs and oxygen-rich air is expelled from the body are known as pulmonary ventilation or breathing.

Gas diffusion across the alveolar membrane is a thin, delicate membrane that separates the air in the alveoli from the blood in the capillaries.

The movement of oxygen and carbon dioxide in the bloodstream between the lungs and other parts of the body is known as gaseous transport by blood.