Respiratory System | quick revision for NEET

Photo By Ai 

- Respiratory System Overview:

- Consists of organs responsible for breathing and gas exchange.

- Includes the nose, nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, lungs, and diaphragm.

- Functions of the Respiratory System:

- Breathing (Ventilation):

- Movement of air in and out of the lungs.

 Oxygen (O2) is taken in, and carbon dioxide (CO2) is expelled.

- Gas Exchange:

- Occurs in the alveoli of the lungs.

- Oxygen from inhaled air diffuses into the bloodstream, while carbon dioxide from the blood diffuses into the alveoli to be exhaled.

- Oxygen Transport:

- Oxygen binds to hemoglobin in red blood cells, which carries it throughout the body to cells and tissues for cellular respiration.

- Carbon Dioxide Transport:

- Carbon dioxide produced by cells is transported in the blood to the lungs, where it is exhaled.

- pH Regulation:

- Regulates blood pH by controlling levels of carbon dioxide, which can combine with water to form carbonic acid, influencing the body's acid-base balance.

- Sense of Smell:

- Olfactory receptors in the nasal cavity detect airborne chemicals, allowing for the sense of smell.

- Respiratory System Structures:

-Nose and Nasal Cavity:

    - Warms, moistens, and filters inhaled air.

  - Pharynx (Throat):

    - Common passageway for air and food.

  - Larynx (Voice Box):

    - Contains vocal cords that produce sound.

    - Functions in speech production and preventing food from entering the airway.

  - Trachea (Windpipe):

    - Conducts air between the larynx and bronchi.

    - Supported by C-shaped cartilage rings to prevent collapse.

  - Bronchi and Bronchioles:

    - Branches of the trachea that conduct air into the lungs.

    - Bronchioles are smaller airways that further divide and lead to the alveoli.

  - Lungs:

    - Paired organs located in the thoracic cavity.

    - Composed of lobes filled with millions of alveoli for gas exchange.

  - Diaphragm:

    - Dome-shaped muscle below the lungs that contracts during inhalation and relaxes during exhalation, aiding in breathing.

- Respiratory System Regulation:

  - Autonomic Control:

    - Breathing is primarily regulated by the respiratory centers in the brainstem, including the medulla oblongata and pons.

    - Automatic processes adjust breathing rate and depth in response to changes in blood pH, oxygen, and carbon dioxide levels.

  - Voluntary Control:

    - Breathing can also be consciously controlled by higher brain centers, allowing for actions such as holding one's breath or altering breathing patterns.

- Respiratory Disorders:

  - Asthma: Chronic inflammation of the airways leading to wheezing, coughing, and difficulty breathing.

  - Chronic Obstructive Pulmonary Disease (COPD): Progressive lung diseases like emphysema and chronic bronchitis characterized by airflow limitation.

  - Pneumonia: Infection of the lungs causing inflammation, fluid buildup, and impaired gas exchange.

  -Lung Cancer: Uncontrolled growth of abnormal cells in the lungs, often linked to smoking and environmental factors.

  - Respiratory Infections: Including influenza, bronchitis, and tuberculosis, caused by viral, bacterial, or fungal pathogens.

Understanding the respiratory system and its functions is crucial for maintaining optimal health and well-being. By nurturing healthy respiratory habits and seeking prompt medical attention for respiratory issues, individuals can support lung function and overall vitality.