The chart shows characteristics of four different groups of invertebrate animals.
Animal
1
2
Characteristics
Has a centralized body cavity,
uses pores and specialized cells
to obtain oxygen from water
Has a soft body and may have a
shel; uses ils or lungs for
obtaining oxygen
Has arms that extend from the
middle of the body, uses tube
feet for obtaining oxygen
Has a segmented body, obtains
oxygen through skin
3
Which set of characteristics describes an echinoderm?
Animal 1
Animal 2
Animal 3
Animal 4

Why is the bond angle in a water molecule less than the bond angle of methane? a. the central oxygen atom in water has two lone pairs of electrons, whereas the central carbon atom in methane has no lone pairs. b. the central hydrogen atom in water has one lone pair of electrons, whereas the central carbon atom in methane has two lone pairs. c. the central oxygen atom in water has four lone pairs of electrons, whereas the central carbon atom in methane has only one lone pair. d. the central oxygen atom exerts more repulsive force on surrounding atoms than the central carbon atom in methane does. reset next