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How do tunicates feed?

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A translucent X-ray fish (Pristella maxillaris) swims in an aquarium, showing its visible backbone and internal structures through its body. — Chordate X-ray fish (*Pristella maxillaris*), is an example of a chordate with a visible backbone.

Tunicates are filter feeders that extract food particles suspended in the water. They utilize a specialized internal mechanism to process these nutrients:1

Water Intake: Water is drawn into the body through an oral (or branchial) aperture by the beating of cilia located on the gill slits within the pharynx.21
Filtration: A glandular organ called the endostyle secretes a sheet of mucus that traps food particles as water passes through the gill slits.1
Digestion: Cilia move this food-rich mucus sheet upward over the gill slits, where it is rolled up and transported to the gut for digestion.1
Exit: After the food is filtered, the water current passes into the atrium and exits the body through the atrial (or cloacal) aperture.21

Depending on their environment, their diet consists of debris from dead plants and animals in shallow waters or plankton in deeper regions.2