Invertebrates 3

Question 1

hydrostatic skeleton

Answer 1

use a cavity filled with water; the water is incompressible, so the organism can use it to apply force or change shape. Plants use osmotic pressure to pressurize the cavity, whereas animals do it with muscle layers in the hydrostat’s walls

Question 2

Its pressurized fluid provides a framework against which muscles act to provide ____ to Annelids

Answer 2

movement

Question 3

nephridia

Answer 3

paired osmoregulatory-excretory organs on the internal body wall of each segment of a worm

Question 4

pharynx

Answer 4

is a tubular pump responsible for sucking bacteria into the worm from outside, concentrating them, and grinding them up

Question 5

Annelid species fall into three main subgroups

Answer 5

Oligochaetes, Polychaetes, Leeches