Cellular Respiration and the Human Respiratory System
The cell uses a portion of the nutrients for manufacturing its own materials. Cellular respiration takes place in the mitochondria. During respiration, a phenomenon of glucose occurs.
Key aspects of cellular respiration:
- Consumption of oxygen occurs during the oxidation of nutrients.
- Liberation of energy allows the cell to perform its functions.
- Production of carbon dioxide and water.
The Respiratory System
The respiratory system is responsible for the exchange of O2 and CO2 gases between the organism and the external environment. It consists of the following:
Airways
Ducts where air flows, divided into two types:
- Upper respiratory tract: Nose, pharynx, and larynx.
- Lower respiratory tract: Trachea, bronchi, and bronchioles, ending in blind sacs called alveoli.
The bronchioles, alveoli, and the network of blood capillaries form the lungs.
Components of the Respiratory System
- Larynx: Has a distinct shape due to the presence of cartilage. The vocal cords are located inside.
- Trachea: A tube that allows air to pass through a series of cartilaginous rings.
- Lungs: Two organs located in the chest cavity, protected by the ribs and supported by the diaphragm.
- Pharynx: During inspiration, air enters the respiratory system through the nose or mouth and passes to the pharynx.
- Bronchi/Bronchioles: Tubes similar to the trachea that branch out like a tree.
- Pulmonary alveoli: Small, thin-walled sacs at the end of the bronchioles, surrounded by a dense network of capillaries.
Gas Exchange
Gas exchange is the process where oxygen moves from the air in the lungs to the blood, and carbon dioxide moves from the blood to the lungs. This occurs in the alveoli through simple diffusion.
Characteristics of Gas Exchange
- The pulmonary alveoli collectively represent a large surface area for exchange.
- The alveoli are surrounded by a dense capillary network.
- The thin membranes separating the blood from the alveolar air allow for the free movement of gases.
Pulmonary Ventilation
Pulmonary ventilation consists of the entry of air into the lungs and the exit of air from the lungs. This is produced by the movement of the thoracic cavity and the diaphragm. It involves inspiration and expiration.
Respiratory Diseases
Infectious Diseases
- Viruses:
- Common cold: Causes a runny nose.
- Flu: Causes high fever and muscle and bone pain.
- Bacteria:
- Pneumonia: Produces severe inflammation of the lungs.
- Tuberculosis: Destroys lung tissue and causes cavities.
Environmental Diseases
These are due to the inhalation of toxic products present in the air due to human activity.
- Silicosis: An occupational disease affecting workers in the ceramic and mining industries, caused by the inhalation of silica particles that crystallize in the lungs, leading to respiratory insufficiency.
- Asbestosis: Due to the inhalation of asbestos, it can lead to cancer.
- Tobacco addiction: The main cause of lung cancer and other respiratory diseases.
- Bronchitis: Irritation of the bronchi due to excess mucus.
- Bronchial asthma: An allergic reaction to pollen or other substances.
- Pulmonary edema: Accumulation of fluid in the alveoli.
- Emphysema: Destruction of the alveolar walls.
Prevention of Respiratory Diseases
Maintaining a healthy lifestyle, exercising, avoiding polluted environments and poorly ventilated enclosed spaces, breathing through the nose instead of the mouth, and wearing a mask when necessary in high-risk occupations are crucial for preventing respiratory diseases.
The Excretory System
The excretory system is responsible for the elimination of waste products from cellular activity. The kidneys perform this function.
Components of the Excretory System
- Kidney cortex: The outermost part with a granular appearance.
- Renal artery: The blood vessel that leaves the kidneys.
- Renal medulla: Includes areas in the shape of a pyramid.
- Urinary bladder: Where urine from the ureters accumulates.
- Kidneys: Two bean-shaped organs located on each side of the spine. This is where urine is formed.
- Ureters: Two tubes that collect the urine produced in each kidney.