Chapter 10 Diversity of Life
How many of the animal phyla include single-celled animals?
0
Most animals fall into one of how many phyla?
9
A multicellular organism that lacks cell walls and obtains energy by eating other organisms is an...
Animal
Which invertebrate animal group is characterized by having a closed circulatory system?
Annelida
Flatworms are most closely related to the...
Annelids
Serial repetition of segments is a defining characteristic of which worm phylum?
Annelids
Which phylum of worms includes the leeches?
Annelids
What defines radial symmetry?
Any plane of symmetry passing through the center of the organism splits it into equal halves.
Which arthropod subgroup includes the spiders?
Arachnids
Which arthropod subgroup includes those with an exoskeleton of chitin?
Arachnids, crustaceans, and insects
A crayfish is a member of the phylum...
Arthropoda
Insects are under what phylum?
Arthropods
The echinoderms are most closely related to the...
Chordates
Hydrae, anemones, and jellyfish are in the phylum
Cnidaria
Some organisms are described as having a ________ digestive tract that includes a mouth at one end and an anus at the other.
Complete
Which cnidarian is the basis of an undersea habitat?
Coral
A sea urchin is a member of the phylum...
Echniodermata
Which one of the following is a defining characteristic of animals but not of plants?
Heterotrophic
Which arthropod subgroup includes those with six legs?
Insects
Oysters are classified in the phylum...
Mollusca
Giant squids are classified as...
Mollusks
Sponges are found...
Mostly in seawater
Which body form of the cnidarians is sessile?
Polyp
Which group of animals is most closely related to the arthropods?
Roundworms
A ________ provides support and protection to arthropods.
Shell
Which of the following animals uses a radula to scrape food into its mouth?
Snail
Gastropods include the...
Snails and slugs
The only animals that lack tissues are...
Sponges
Which of the following animal phyla is distinguished by a lack of tissues?
Sponges
Cnidarians are named for their cnidocytes, a feature unique to the group. What are cnidocytes?
Stinging cells
Many, though not all, mollusks have a shell. What secretes the shell?
The mantle
What happened during the Cambrian explosion?
There were a rapid diversification of animal forms.
How do sponges (and starfish) acquire their nourishment?
They filter it from seawater
What acts as both a circulatory system for gas exchange and a hydraulic system for movement in the echinoderms?
Water vascular system
