RESPIRATION  AND   BREATHING

CLASS: X   SUBJECT : SCIENCE ( LIFE SCIENCE )

BREATHING   BREATHING is an ordinary term

generally used by common people .It means simply the taking in of oxygen and giving out carbon dioxide i.e. simply the exchange of gases .Taking in of oxygen is known as INHALATION & elimination of carbon dioxide Is called EXHALATION. Every living organism breathe except some anaerobic microbes.

RESPIRATION  RESPIRATION is one of the basic &

essential life processes.It is concerned with the release of energy from food ( Hexose sugar )in the form of ATP molecules.The term is much broader than Breathing.In higher animals & plants it involves 3 steps :

1. Oxygen is taken in by the process of INHALATION.

2. The inhaled oxygen is transported to each & every cell of the body in case of multicellular plants & animals & in the case of unicellular plants & animals like bacteria or Amoeba, Paramecium  etc. it is directly taken by diffusion. What you need to understand is that the inhaled oxygen is transported to all the cells of the body. Now there is a part of a cell  known as "MITOCHONDRIA" who plays the main role of release of energy from food.Therefore it is also known as POWER HOUSE of a cell. The reaction between hexose sugar (simplest 6 carbon sugar like glucose, dextrose etc.) & oxygen is carried out in Mitochondria and after the formation of various intermediate Products the carbon dioxide & water is formed as the final end product. During this complete oxidation of one molecule of 6 Carbon sugar (hexose) 38 ATP molecules are produced.

At this stage some elementary idea about the ATP should be made clear to you.Adenosine is a chemical present in our muscles & tissues. When it is bonded with 2 atomsOf inorganic phosphorus(Pi),then it is molecule of ADP means Adenosine diphosphateNow the energy released during respiration is used to bind one more inorganic phosphorus(Pi) to ADP with the formation of ATP molecule. In this way energy is captured in ATP molecule During Respiration. The equation can be expressed in the following way....

ADP{adenosine di phosphate} + Pi. = . ATP { Adenosine tri phosphate }

3. Since carbon dioxide is harmful for the body it is being eliminated outside the body byThe process of EXHALATION which is the last stage of Respiration. Now it is clear that the basic process of Respiration is concerned with the release of energy & this is carried out in the cell organelle Mitochondria. There Mitochondria is known as the POWERHOUSE of the cell.If release of energy takes place in the presence of oxygen as described above then thisProcess is known as ANAEROBIC RESPIRATION & Organisms are called as AEROBES.If energy is released from food without oxygen then the process is called as ANAEROBIC RESPIRATION & organisms are known as ANAEROBES.

In anaerobic respiration there is incomplete oxidation of food & Ethyl alcohol (Anaerobic Breakdown of sugar by Yeast) in plants & lactic acids in muscles of animals is produced.Carbon dioxide gas and only 2 molecules of ATP are released by the incomplete oxidationOf glucose molecule.

DECLARATION :

I Want to declare one thing in the end that the topic is purely my own expression and no part has been taken from any site or any book.Valuable suggestions are welcome from Esteem members of  Learn bazar , Parents, Teachers & Students.

Prepared by... ASHOK MEHTA