By having a unicellular form, a protist will gain two major advantage:
1. It would be able to reproduce on its own, asexually without having to look for sexual partners. It will be able to reproduce by binary fission, multiple fission or budding.
2. It will benefit from a simple body system that does not need system specialization. Having specialized systems with many parts can results in some of the system having problems at times.
This phenomenon is a pain from the gallbladder. The pain of gallbladder illness nearly at all times has one of two reasons - gallstones or cholecystitis. Gallstones are stones that is created in the gallbladder. They differ in extent from a millimeter or two to a number of centimeters and are from cholesterol or bile colorings. Cholecystitis means swelling of the gallbladder. Even if, cholecystitis is most normally triggered by gallstones, there are other less common reasons too.
Alveoli have a rich supply of blood capillaries where diffusion of oxygen takes place . oxygen combines with haemoglobin to form oxyhaemoglobin which is then carried to different cells tissues and body parts.
so the structure is alveoli
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