Which of the following is correct regarding acclimatization? A. Decreases in arterial POâ cause the peripheral chemoreceptors to become less responsive to increases in PCOâB. At high altitudes, hemoglobin's affinity for Oâ is increased because BPG concentrations increase. C. When blood Oâ levels decline, the kidneys produce more erythropoietin, which stimulates breakdown of red blood cells in the spleen D. High-altitude conditions always result in lower-than-normal hemoglobin saturation levels because less Oâ is available to be loaded

D. High-altitude conditions always result in lower-than-normal hemoglobin saturation levels because less Oâ is available to be loaded

Explanation:

Acclimatization is a process in which body of organisms adjust itself according to the conditions of the environment. This process occurs for a short period of time. At normal altitude, hemoglobin saturation levels becomes high. When a person goes to a high altitude, the hemoglobin saturation levels decreases because oxygen is a heavier gas and we go higher its concentration reduces in the atmosphere.

voluntary muscles are controlled by the cerebellum.

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.