6th Grade Science Test 4 Flashcards
most crustaceans have how many body regions
three
when the head and thorax are joined together, the body region is called the
cephalothorax
many crustaceans have ___ legs
ten
most crustaceans breathe with
gills
a centipede has __ pair(s) of legs on most body segments
one
the pair of legs closest to the centipede’s ___ is always poisonous
mouth
by releasing poison through the stink glands along the sides of its body near its many legs, the ___ defends itself
millipede
Worms are not arthropods because they do not have a(n) _____, a protective outer covering.
exoskeleton
earthworms enrich the soil with their
castings
the stiff bristles on the body of the earthworm
setae
the threadlike structures in an cell that determine the characteristics of the organism and how it runs
chromosomes
the structure that surrounds the cell and protects it
cell membrane
the jellylike fluid that fills the cell
cytoplasm
the structure that directs the work of the cell
nucleus
using its foot as if it were sliding on its stomach allows a ___ to move
gastropod
mussels, oysters, clams, and scallops are all ___, mollusks having two matching shells
bivalves
the snail is part of a group of one-shelled mollusks called
bivalves
five or more rays, each with two rows of tube feet, are formed on the
sea star
an invertebrate that builds a protective limestone cup at the base of its body
coral polyp
the tiniest crab
pea crab
