Biology Exam 3
Earthworms are in the phylum _____.
Annelida
Grasshoppers are classified in the phylum _____.
Arthropoda
While on a biological expedition, you discover a new species with the following characteristics: has an exoskeleton, exhibits bilateral symmetry, and has jointed appendages. What phylum does this newly discovered organism belong to?
Arthropoda
The _____ explosion occurred approximately 545 million years ago.
Cambrian
A sea star and a hookworm belong to the phyla _____ and _____, respectively.
Echinodermata ... Nematoda
______ are the most diverse group of arthropods.
Insects
Snails are classified in the phylum _____.
Mollusca
Roundworms are classified in the phylum _____.
Nematoda
All animals can trace their lineage to a common ancestor that lived in the _____.
Precambrian
How do sponges differ from all other animals?
Sponges lack true tissues.
Why are annelids, arthropods, and mollusks placed in the same clade?
They are protostomes.
Which of these statements is true of earthworms?
They have a digestive system with two openings.
Which of these statements is true of sponges?
They have no true tissues.
A distinguishing feature of vertebrates is the presence of _____.
a backbone
One body plan, called bilateral symmetry, represents a major branch point in animal evolution and can be described as __________.
a body plan with only one way to split it into two equal halves—right down the midline
Which of the following is associated with bilateral symmetry?
a definite "head end"
Which of the following is radially symmetrical?
a doughnut
Which of the following is an invertebrate?
a sponge
Insects, such as the grasshopper shown below, have ______.
a three-part body: head, thorax, and abdomen
What characteristic is unique to echinoderms?
a water vascular system
According to this phylogenetic tree, the animals most closely related to reptiles and mammals are _____.
amphibians
Which of these characteristics is common to both snails and earthworms?
an alimentary system with two openings
Which of these characteristics is shared by both dogs and sea stars?
an endoskeleton
The legless, segmented body of the animal below suggests that it is a(n) ______.
annelid
Annelids __________.
are segmented worms
Members of the phylum Mollusca __________.
are soft-bodied and usually covered by a shell
According to this phylogenetic tree, annelids are most closely related to _____.
arthropods
There are more species of ______ than of any other type of animal.
arthropods
Flatworms are the simplest animals with __________.
bilateral symmetry
Which anthropoids are most closely related to humans?
chimpanzees
The arthropod skeleton is composed of ______.
chitin
What name is given to the food-trapping cells of sponges?
choanocytes
Echinoderms are _____.
deuterostomes
Sea stars and sand dollars belong to a group of spiny marine animals called _____.
echinoderms
Annelids, such as the leeches, __________, a characteristic shared by all other bilateral animals except flatworms.
exhibit a complete digestive tract
As adults, sea stars _____.
exhibit radial symmetry
Sponges feed by __________.
filtering small particles from water
The figure below shows a planarian. Bilateral symmetry, the leaflike shape, and the highly branched gastrovascular cavity all suggest that the planarian is a(n) ______.
flatworm
Consider the following list of animals: giant squid, earthworm, largemouth bass, snail, tapeworm, coral, and sea star. The two that belong to the same phylum are the __________, and their phylum is _____.
giant squid and snail ... Mollusca
Flatworms are similar to cnidarians in that both ______.
have true tissues
What does the term tetrapod mean?
having four feet
Earthworms are most closely related to _____.
leeches
The mobile stage of the cnidarian life cycle is the ______ stage.
medusa
According to this phylogenetic tree, the clade that includes echinoderms and chordates is most closely related to the clade that includes _____.
molluscs
Annelids are most closely related to ______.
molluscs
The water vascular system of a sea star functions in __________.
movement of the tube feet
A(n) ______ is an example of a mollusc that does not have a shell.
octopus
Molluscs are _____.
protostomes
What type of symmetry does this organism exhibit?
radial
Cnidarians are in the _____ clade.
radiata
Nematodes are most closely related to _____.
rotifers
A characteristic of arthropods that has allowed for their great success is the presence of ______.
specialized segments
Grasshoppers respire via _____.
spiracles and tracheae
Which of the following are found in members of the phylum Cnidaria?
stinging cells, radial symmetry
A characteristic of cnidarians is __________.
tentacles with stinging cells
In arthropods, molting is necessary because __________.
the chitinous exoskeleton cannot grow
The phrase "Cambrian explosion" refers to __________.
the rapid adaptive radiation that gave rise to most extant animal phyla
Which of these is a characteristic of sea stars?
tube feet
