AEROBIC RESPIRATION: Lungs Respiration in Humans

AEROBIC RESPIRATION: Lungs Respiration in Humans

Respiratory system
LUNGS INTRODUCTION Lungs Diaphragm Structure of the Lungs Lungs Breathing Aerobic Respiration Diseases of the Lungs Lung Abscess Lung Biopsy Lung Cancer Lung Cancer, Non-small Cell Lung Cancer, Small Cell Lung diseases chemical exposure Lung Perfusion and Ventilation Lung Surgery Lung Transplantation

Nasal Passages Pharynx Larynx Trachea, Bronchi, and Bronchioles Alveoli RESPIRATORY REGULATION HAZARDS Bronchodilators Bronchoscopy Laryngoscopy Laryngectomy
Respiratory Diseases Asthma Aspergillosis Bronchal Adenoma Bronchitis Bronchiectasis Byssinosis Cough Emphysema Hantaviruses Hay Fever Laryngeal Cancer Laryngitis Lung Cancer Nasal Polyps Pneumonia Respiratory Failure Tuberculosis
LIVER LIVER DISEASES FUNCTIONS OF THE LIVER STRUCTURE OF THE LIVER
Circulatory system Digestive system Endocrine system
Glandular Structure Gonads Hormones Pancreas Parathyroid Glands Pineal Gland Pituitary Gland Pituitary Hormones Thymus Thyroid Gland

AEROBIC RESPIRATION

In the life-supporting process of aerobic respiration, oxygen from incoming air enters the blood; and carbon dioxide, a waste gas from the metabolism of food, is exhaled into the atmosphere. Air entering the lungs contains about 21 percent oxygen and 0.04 percent carbon dioxide. Air leaving the lungs contains about 14 percent oxygen and about 4.4 percent carbon dioxide. The composition of the air changes between inspiration and expiration, when the air is deep in the lung tissue.

The exchange of gases takes place when air reaches the alveoli. These small sacs are only one cell thick, and they are surrounded by blood capillaries that are also only one cell thick. Air diffuses through these cells into the capillary blood, which carries the oxygen-rich air to the heart to be distributed throughout the body. In the alveoli, at the same time, gaseous carbon dioxide diffuses from the blood into the lung and is expired.