The meal begins outside
The sea star grips the two halves of the mussel’s shell, called valves, with its tube feet. If they part just a little, the sea star can extend its stomach through its mouth and begin digesting the soft tissue inside.
Two openings, one current
Water enters through a tube called the incurrent siphon. It passes through the branchial basket, a perforated part of the sea squirt’s throat, and leaves through the excurrent siphon. Tiny beating hairs called cilia help keep the water moving.
A net made of mucus
Inside the throat, mucus traps food particles. The water flows on towards the outlet, while the mucus carries its catch towards the oesophagus.
