Chapter - 2.1-Life Processes in living Organisms – Part -1

Chapter - 2.0

Life Processes in living Organisms – Part -1

« Living Organisms and life processes: -

 

• Various Organ system continuously performs function in human body
• Digestive, respiratory, circulatory, excretory.
• Carbohydrates, fats and lipids are the main source of energy
• It is harvested by mitochondria present in each cell.
• Foodstuffs and oxygen are transported up to cell via circulatory system.
• Plants are autotrophs
• They prepare their own food.
• They utilize some of the food for themselves remaining is stored in various parts like fruit, leaves, steam, roots etc.
• We consume nutrients from plants like carbohydrates, fats, proteins, vitamins, mineral etc.

 

« Material we consume from Animals and plants: -

 

• Different nutrients like carbohydrates, fats, proteins, vitamins, minerals, etc. from various plants materials.
• We obtain the carbohydrates from milk, fruits, jaggery, sugar cane, vegetables potatoes, sweet potatoes, sweet, meats.
• Cereals like wheat, maize, ragi, jowar, millet, rice etc.
• We get 4 cal energy per gram of carbohydrates.

«Living Organisms and Energy production: -

•       In Living Organisms, Respiration occurs at Two levels

  i)                   Body

  ii)                 Cellular level

•         Oxygen and carbon dioxide are exchanged.

•         In case of respiration at cellular level,  foodstuffs

•       Foodstuffs are oxidized either with or without help of oxygen.

•         Carbohydrates  of the food that we consume is used foe energy required for daily need.

•       Energy is obtained in from of ATP.

•       Glucose is oxidized step by step in the cells this is called as cellular respiration.

 

­­­­­                                     Cellular Respiration

 

    Aerobic Respiration                                         Anaerobic Respiration

(Oxygen is involved)                                            (Oxygen is not involved)

In aerobic respiration glucose is oxidized in 3 steps

1)        1) Glycolysis :-

• Process of glycolysis occurs in cytoplasm.
• 
  
• A molecule of glucose is oxidized step by step
• 
  
• Two molecules of each. Pyruvic acid, ATP, NADH2 and water is formed.
• 
  
• Pyruvic acid are converted into molecules of Acetyl-Coenzyme-A.
  Two molecules of NADH2 and Two molecules of CO2 are released durig this process.

2) Tricarboxylic acid cycle:-

• Cyclic chain of reactions called as tri caboxylic acid cycle
• It is operated in the mito chondria
• Acetyl part of acetyl-CoA is completely
• CO2, H2O , NADH2, FADH2, are derived.

 

3) Electron Transfer Chain reaction: -

• Due to this 3 molecules of ATP are obtained from each NADH2 molecule and 2 molecules of ATP from each FADH2 molecule
• Water molecules are also formed in this reaction
• Electron transfer chain reaction is separated  in mitochondria only

Full form of

NADH2 – Nicotinamide Adenine Dinucleotide

FADH2 – Flavin Adenine Dinucleotie

Both enzymes are formed in the cells and used in cellular respiration