Respiration in Organisms
Respiration is a vital biological process that occurs in all living organisms. It is the
process by which food (glucose) is broken down in the cells of the body with the
help of oxygen to release energy. This energy is essential for various life activities.
Cellular Respiration: The process of breakdown of food in the cell with the
release of energy is called cellular respiration.
1. Types of Respiration
Based on the presence or absence of oxygen, respiration is classified into two
types:
A. Aerobic Respiration
When the breakdown of glucose occurs with the use of oxygen, it is called aerobic
respiration. It is the most common form of respiration in higher organisms,
including humans.
Glucose + Oxygen → Carbon Dioxide + Water + Energy
B. Anaerobic Respiration
When the breakdown of glucose occurs without the use of oxygen, it is called
anaerobic respiration. This occurs in organisms like yeast and sometimes in our
muscles during heavy exercise.
Glucose → Alcohol + Carbon Dioxide + Energy (In Yeast)
Glucose → Lactic Acid + Energy (In Muscles)
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Respiration is a vital biological process that occurs in all living organisms. It is the
process by which food (glucose) is broken down in the cells of the body with the
help of oxygen to release energy. This energy is essential for various life activities.
Cellular Respiration: The process of breakdown of food in the cell with the
release of energy is called cellular respiration.
1. Types of Respiration
Based on the presence or absence of oxygen, respiration is classified into two
types:
A. Aerobic Respiration
When the breakdown of glucose occurs with the use of oxygen, it is called aerobic
respiration. It is the most common form of respiration in higher organisms,
including humans.
Glucose + Oxygen → Carbon Dioxide + Water + Energy
B. Anaerobic Respiration
When the breakdown of glucose occurs without the use of oxygen, it is called
anaerobic respiration. This occurs in organisms like yeast and sometimes in our
muscles during heavy exercise.
Glucose → Alcohol + Carbon Dioxide + Energy (In Yeast)
Glucose → Lactic Acid + Energy (In Muscles)
Page 1
