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RESPIRATION:-
Respiration: The process of breakdown of glucose into CO₂, H₂O and Energy is called respiration. OR The breakdown of glucose to form energy is called respiration. Respiration reaction is as follows: Types of respiration- Aerobic Respiration Anaerobic Respiration i) Respiration occurs in the presence of oxygen. ii) Complete break down of food takes place. iii) It occurs in mitochondria. iv) More energy released. v) End products are CO₂ & H₂O. i) Respiration occurs in the absence of oxygen. ii) Partial break down of food takes place. iii) It occurs in yeast and muscle cells. iv) Less energy released. v) End products are CO₂, ethanol & lactic acid. Aerobic Respiration/ Cellular Respiration: - The respiration which is occurred in the presence Oxygen is called Aerobic respiration.
Anaerobic Respiration is of following types:- a) Alcoholic or Ethanol Fermentation: - It is an anaerobic respiration in which Ethanol is released. b) Lactic Acid Fermentation: - It is an anaerobic respiration in which Lactic acid is released. V.IMP Various pathways for breakdown of glucose:- Important NOTE:- ►Site for aerobic respiration- Mitochondria. ►The first step of respiration is break down of glucose (6-carbon molecule) into pyruvate (3-carbon molecule) take place in - Cytoplasm.
RESPIRATION IN HUMAN BEINGS
i) Air is taken into the body through the nostrils. The air passing through the nostrils is filtered by fine hairs that line the passage. The passage is also with mucus which helps in filtering. ii) Then, the air passes through the throat and into the lungs. Rings of cartilage are present in the throat which ensure that the air passage does not collapse. iii) The trachea (the wind pipe) runs down and divides into two tubes like structure called bronchi. Each bronchi then enters into a lung and divides into smaller and smaller tubes called bronchioles. They finally terminate into balloon-like structures called alveoli (OR) alveolar sac , where gases exchange takes place. iv) During breathe in , ribs move up and diaphragm flattened so that air is sucked into lungs and fills the expanded alveoli. v) Haemoglobin binds with the oxygen and carries with the blood in the body. The oxygen from the blood diffuses into all parts of the body where it combines with food to produce CO2 and energy. This CO2 diffuses into the blood and is carried to the lungs for exit. vi) Ribs moves down and diaphragm becomes relax. So, CO2 comes out.
Important NOTE:- ► Site for exchange of gases take place in human - Alveoli ►Rings of cartilage are present in the trachea which ensure that the air passage does not collapse. ►Common passage for food and air - Oropharynx. ► Epiglottis: - It is a leaf shaped flap in the trachea that prevents food from entering into trachea and lungs.
