Respiration in Plants

Respiration is the process by which cells produce energy by breaking down glucose. In plants, respiration provides the energy for growth, repair, and other life processes.  

Steps of Respiration in Plants  

1. Gas Exchange: Taking in oxygen and releasing carbon dioxide.  

2. Breakdown of Glucose: Glucose molecules are broken down to release energy.  

Types of Respiration  

- Anaerobic Respiration (without oxygen):  

  Glucose --> Ethyl Alcohol + Carbon dioxide + Energy 

  - Occurs in bacteria, fungi, and microbes.  

  - Known as fermentation.  

  - Produces less energy compared to aerobic respiration.  

- Aerobic Respiration (with oxygen):  

  Glucose + Oxygen --> Carbon dioxide + Water + Energy  

  - Produces a large amount of energy (about 674 kilocalories per mole of glucose).  

  - Occurs in the mitochondria.  

Respiration Sites in Plants  

- Stomata: Tiny openings on leaves.  

  - Open during the day, closed at night.  

  - Allow gaseous exchange (oxygen and carbon dioxide).  

- Lenticels: Small openings on the bark of woody stems and roots of dicot plants.  

  - Enable direct gas exchange between internal tissues and the external environment.  

  - Bark itself does not allow gases to pass through.  

Key Points  

- In anaerobic respiration, glucose is incompletely broken down in the cytoplasm.  

- In aerobic respiration, glucose is completely broken down in mitochondria, releasing carbon dioxide, water, and energy.  

- Both processes ensure plants have the energy required for survival and growth.