The bicuspid valve is also known as the:

The opening of the Aortic valve is initiated when the:

The mitral, tricuspid and both semilunar valves are all closed during which of the following?

The vagus nerve:

In amphioxus, the ___ organ inside the oral hood is covered in cilia. Beating of these cilia produces a vortex of water inside the hood.

Of the four extraembryonic membranes of reptiles, birds, and mammals, the ___ surrounds the embryo in its own “private pond.”

Unlike gars, most modern bony fish have a ___ swim bladder. In this kind of swim bladder, the organ is not connected to the digestive tract by a pneumatic duct.

Clamworms and other polychaetes have flap-like appendages called ___. These appendages are uses for locomotion and gas exchange. 

On a dark and stormy night, two earthworms meet outside their burrows. Sperm leaves the male pore of one worm before traveling down the seminal ___to the seminal receptacles of the other worm.

Amphioxus (lancelets) belong to subphylum ___.