What system maintain the ph of human blood at very near 7.4?

Buffer systems in our body maintain the pH of blood to be at an optimum level which is at a range of 7.3-7.4. A buffer is a solution that resists changes in pH during the addition of an acid or a base. Our blood has a number of buffer systems. Examples are the bicarbonate buffer system and the hemoglobin buffer system.

organisms are more likely to be more preserved in mud than sand because mud is moist and wet, while sand is very dry.