: Most species live in the ocean, ranging from tropical coral reefs to polar waters and even deep-ocean trenches. They often encrust rocks, shells, and kelp.
: They possess a U-shaped digestive tract with both a mouth and an anus. Because the anus is located outside the tentacle crown, they are also known as Ectoprocta ("outside anus").
, commonly known as "moss animals," are a phylum of microscopic aquatic invertebrates that live in sedentary colonies. While they are often mistaken for coral, seaweed, or even gelatinous "blobs," they are a distinct group of filter-feeders found in both marine and freshwater environments. Biological Structure and Anatomy bryozoa
Bryozoan colonies are made up of individual units called . These zooids are typically less than 1 millimeter long and cooperate to ensure the colony's survival.
: In many marine species, zooids are specialized for different tasks, such as feeding ( autozooids ), defense ( avicularia ), or cleaning the colony ( vibracula ). Habitat and Environment : Most species live in the ocean, ranging
: These species often form large, jelly-like masses that can grow to the size of a football. Finding them in a pond or lake is often a sign of good water quality , as they help clear the water by filtering silt and clay. Bryozoans (Moss Animals)
: Zooids secrete a protective chamber called a zooecium, which can be gelatinous, chitinous (like insect shells), or calcified (like coral). Because the anus is located outside the tentacle
: Each zooid has a "crown" of ciliated tentacles called a lophophore used to filter food like phytoplankton and bacteria from the water.