Mollusks have four distinct body parts: a foot, a head, a visceral mass, and a tail. true or false

This is statement is not true.

The distinct parts of  mollusks are three body zones namely a head-foot, visceral mass and a mantle. In some mollusks, a forked post - anal tail may be seen but it is  not a distinct feature in all mollusks.

Common features of  mollusks include:

1. Unsegmented  soft body with bilateral symmetry.

2.Presence of internal or external shell.

3. Toothed tongue called the radula.

4. Mantle

5. Muscular foot

6. Fluid filled cavity called  coelom

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.