Respiratory System

A leaf-shaped flap of cartilage located behind the tongue, at the top of the larynx or voice box, is called the Epiglottis.

Its crucial role is to cover the windpipe (trachea) during swallowing, preventing food and liquids from entering the lungs.

The maximum possible volume of air, which can be inhaled by humans, is called Vital lung capacity.

• It represents the greatest volume of air that can be expelled from the lungs after a maximum inhalation, indicating the maximum amount of air that can be exchanged during a single breath.

The number of RBCs increases if one lives at higher altitudes because There is less oxygen in mountains.

• At higher altitudes, the atmospheric pressure and partial pressure of oxygen are lower.
• To compensate for this reduced oxygen availability, the body produces more red blood cells to carry sufficient oxygen to the tissues.

The part of the fish body that helps them to breathe in water is the Gill.

• Gills are specialized respiratory organs in fish that extract dissolved oxygen from water and release carbon dioxide, performing the function analogous to lungs in terrestrial animals.

The covering of the lungs is called the Pleural membrane.

• Each lung is enclosed by a double-layered serous membrane called the pleura.
• The outer parietal pleura lines the thoracic cavity, and the inner visceral pleura covers the lung surface, with a lubricating fluid in between that reduces friction during breathing.

If the concentration of CO₂ in the blood increases, then the breathing is Increases.

• An increase in blood CO₂ concentration leads to a decrease in pH (more acidic blood).
• This change is detected by chemoreceptors, which stimulate the respiratory center in the brain to increase the rate and depth of breathing to expel excess CO₂.

Cartilaginous discs prevent the collapsing of the trachea.

The trachea (windpipe) is reinforced by C-shaped rings of hyaline cartilage, which provide structural support and keep the airway open, ensuring continuous airflow to and from the lungs.

By the complete aerobic respiration of one molecule of glucose, 38 molecules of ATP are typically obtained.

• This includes ATP generated during glycolysis, the Krebs cycle, and oxidative phosphorylation.
• In some eukaryotic cells, the net yield can be 36 ATP due to the cost of transporting NADH into the mitochondria.

The part of the human body that releases Carbon dioxide, brought in by the blood, from the rest of the body is Alveoli.

• These tiny air sacs in the lungs are the primary sites of gas exchange, where carbon dioxide diffuses from the blood into the alveoli to be exhaled, and oxygen diffuses from the alveoli into the blood.

• It is a metabolic process that occurs in the absence of oxygen to produce energy (ATP).
• This process is less efficient than aerobic respiration and often produces byproducts like lactic acid or ethanol.