What are the four processes of respiration? be sure to define ventilation?

Respiration is an catabolic process in which the organic compounds are oxidized to release energy, carbon dioxide and water. The liberated energy is stored in the ATP molecules (adenosine triphosphate), which are the energy currency of the cells. The four basic processes involved in respiration are-

(1) Pulmonary ventilation or breathing- It is the process of inflow of air into the lungs from the atmosphere (inspiration or inhalation) and outflow of air from the lungs to the atmosphere (expiration or exhalation). It is due to the difference in the air pressures according to the principle of Boyle's law.

(2) External respiration- It is the process of exchange of the oxygen and carbon dioxide between the inhaled air in the alveoli of the lungs and the deoxygenated pulmonary blood.

(3) Internal respiration- It is the process of exchange of gases between the oxygenated blood and the tissue cells of the body.

(4) Cellular respiration- It is the process of oxidation of the respiratory substrates like glucose inside the cells.

Thus, the four processes of respiration include the pulmonary ventilation, external respiration, internal respiration and cellular respiration.

estuaries are the partially enclosed coastal bodies of brackish water formed at the mouth of sea where river meets an ocean. it is a transition zone between river and sea water so estuaries are influenced to both marine environment such as tides, waves and to riverine such as flow of fresh water and sediments. the mixing of sea and fresh water provide high level of nutrients, making estuaries a high product habitats.

many estuaries suffers degradation from a variety of human activities like erosion from deforestation, overgrazing, overfishing, drainage and eutrophication.

so from the above statement answers will be

1. false as estuaries are formed due to both brackish and freshwater.

2.true, due to high productivity estuaries are breeding ground for many marine species.

3. direct and indirect activities of man that contribute to pollution and deposition of sediments.