How do angelfish breathe?

Angelfish, like all fish, breathe through their gills. Gills are respiratory organs that extract oxygen from water. Angelfish have four pairs of gills, located on either side of their head. Each gill is made up of a series of thin, feathery filaments that are covered in tiny blood vessels. As water passes over the gills, the oxygen in the water diffuses into the blood vessels and is transported throughout the body. Carbon dioxide, a waste product of cellular respiration, is released from the blood into the water.

Angelfish use a variety of adaptations to maximize the efficiency of their gills. For example, they have a large gill surface area, which allows them to extract more oxygen from the water. They also have a high heart rate, which helps to pump blood quickly through the gills. And they have a thin, flexible body that helps them to move through the water easily, reducing the amount of energy they need to expend on swimming.

Angelfish are able to breathe air, but they do so only when they are in distress. When an angelfish is in air, it will gasp for air and may even jump out of the water. This is because the gills of an angelfish are not as efficient at extracting oxygen from air as they are at extracting oxygen from water.