Respiration

Respiration is the process of obtaining oxygen from outside the body and using it in the breakdown of food sources for cellular demands.

Sub-processes of Respiration

• Breathing: Gaseous exchange – intake of oxygen and release of CO2
• Cellular respiration: Simple food is broken down to release energy within the cell

 Steps Involved In Respiration

• Breaking down glucose into pyruvate: 

This process occurs in the cytoplasm. Pyruvic acid is formed when glucose molecules are broken down. The carbon atoms in the glucose molecule are six, while the carbon atoms in pyruvic acid are three.

• The fate of Pyruvic Acid: 

In mitochondria, further breaking down of pyruvic acid takes place and the molecules formed depend on the type of respiration in a particular organism. Respiration has two types, viz. aerobic respiration and anaerobic respiration.

Aerobic Respiration:

• It happens when there is oxygen present
• Carbon dioxide is produced when pyruvic acid is transformed
• Water molecules are created as well as energy is released

Anaerobic Respiration:

• It happens when there isn’t any oxygen in the air
• Pyruvic acid is transformed into lactic acid or ethyl alcohol
• Ethyl alcohol is usually formed in microbes, like yeast or bacteria
• Lactic acid is formed in some microbes as well as in muscle cells
• Break-down of glucose by various pathways

The energy generated during cellular respiration is immediately used to synthesize ATP, which is used to fuel all of the cell’s other operations.

ATP

• Most cellular functions use ATP as their energy currency
• From ADP and inorganic phosphate, the energy released during breathing is utilized to create an ATP molecule
• Endothermic processes in the cell use ATP to drive the reactions
• The energy released by ATP is 30.5 kJ/mol
• It can be used in the cells for the contraction of muscles, protein synthesis, conduction of nerve impulses, and many other activities

Respiration in Humans

• The nostrils are the passages via which air enters the human body
• Fine hairs that line the channel filter the air that passes through the nostrils
• Mucus also lines the passage, which aids in the process
• The air then enters the lungs after passing via the throat
• The presence of rings of cartilage in the neck prevents the airway from collapsing

• The pathway within the lungs divides into smaller and smaller tubes that eventually terminate in balloon-like structures known as alveoli (singular-alveolus)
• The alveoli provide a surface where the exchange of gases can take place
•  The alveoli’s walls are lined with a dense network of blood vessels
• During inhalation, ribs are lifted, and the diaphragm gets flattened
• The chest cavity becomes larger as a result and thus air is sucked into the lungs and fills the expanded alveoli
• Blood delivers carbon dioxide from the rest of the body to the alveoli, while alveolar blood vessels capture oxygen from the alveolar air and transport it to all of the body’s cells
• The respiratory pigment in humans is haemoglobin, which has a strong affinity for oxygen
• This pigment can be found in red blood cells (RBC)

Smoking is Injurious to Health

• Lung cancer is one of the most common causes of death in the world
• The upper part of the respiratory tract is provided with small hair-like structures called cilia
• These cilia help to remove germs, dust, and other harmful particles from inhaled air
• Smoking destroys these hairs due to which germs, dust, smoke, and other harmful chemicals enter the lungs and cause infection, cough, and even lung cancer
  

   

   

Conclusion

The current article describes the respiration process in plants as well as human beings. The article also covers different types of respiration i.e., aerobic as well as anaerobic respiration. While the aerobic process deals with respiration in the presence of oxygen, the anaerobic process is about respiration in the absence of oxygen. While ATP is the energy currency of the cell, it is made by mitochondria and hence mitochondria are called the powerhouse of the cell.  Further, the harmful effects of smoking are also discussed. The terms unexplained in the body part are covered in the FAQs section.