Arrow Worms

question 38

Multiple Choice

Arrow worms

• A) were once thought to be deuterostomes based on their development.
• B) have a circulatory system.
• C) are definitely the closest relatives of the lophotrochozoans.
• D) have two sexes.
• E) have a distinct larval stage.

---

Definitions:

Left Atrium

A chamber out of the heart's four, it takes in blood enriched with oxygen from the lungs and propels it toward the left ventricle.

Blood Flow

The continuous circulation of blood through the cardiovascular system, delivering oxygen and nutrients to tissues and organs.

Regurgitate

The act of bringing food back up into the mouth or esophagus after it has been swallowed, sometimes without re-chewing.

Leaking Valve

A malfunction in a valve that allows fluid or gas to escape unintentionally.