Ch.33 - InvertebratesSee all chapters
All Chapters
Ch.1 - Introduction to Biology
Ch.2 - Chemistry
Ch.3 - Water
Ch.4 - Carbon
Ch.5 - Biological Molecules
Ch.6 - Cells
Ch.7 - The Membrane
Ch.8 - Energy and Metabolism
Ch.9 - Respiration
Ch.10 - Photosynthesis
Ch.11 - Cell Signaling
Ch.12 - Cell Division
Ch.13 - Meiosis
Ch.14 - Mendelian Genetics
Ch.15 - Chromosomal Theory of Inheritance
Ch.16 - DNA Synthesis
Ch.17 - Gene Expression
Ch.18 - Regulation of Expression
Ch.19 - Viruses
Ch.20 - Biotechnology
Ch.21 - Genomics
Ch.22 - Development
Ch.23 - Evolution by Natural Selection
Ch.24 - Evolution of Populations
Ch.25 - Speciation
Ch.26 - History of Life on Earth
Ch.27 - Phylogeny
Ch.28 - Prokaryotes
Ch.29 - Protists
Ch.30 - Plants
Ch.31 - Fungi
Ch.32 - Overview of Animals
Ch.33 - Invertebrates
Ch.34 - Vertebrates
Ch.35 - Plant Anatomy
Ch.36 - Vascular Plant Transport
Ch.37 - Soil
Ch.38 - Plant Reproduction
Ch.39 - Plant Sensation and Response
Ch.40 - Animal Form and Function
Ch.41 - Digestive System
Ch.42 - Circulatory System
Ch.43 - Immune System
Ch.44 - Osmoregulation and Excretion
Ch.45 - Endocrine System
Ch.46 - Animal Reproduction
Ch.47 - Nervous System
Ch.48 - Sensory Systems
Ch.49 - Muscle Systems
Ch.50 - Ecology
Ch.51 - Animal Behavior
Ch.52 - Population Ecology
Ch.53 - Community Ecology
Ch.54 - Ecosystems
Ch.55 - Conservation Biology


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Porifera and Cnideria
Additional Problems
An evolutionary advance that first appeared in echinoderms wasa. radial symmetryb. one-way digestive systemc. external digestiond. endoskeleton
The "spiny skin" for which echinoderms are named refers to thea. extended skin gillsb. protruding tube feetc. rigid tentaclesd. chitinous exoskeletone. calcium-rich endoskeleton
The only living echinoderms that are fully sessile are thea. sea liliesb. brittle starsc. feather starsd. sand dollarse. sea cucumbers
Some sea stars digest bivalve mollusksa. in the mouth regionb. in the mollusk shellc. within their gastrovascular cavityd. in a digestive space in the central diske. in their water vascular system
The _______________ comprise the largest class of echinoderms in terms of numbers.a. brittle starsb. sand dollarsc. sea urchinsd. sea liliese. sea stars
Sea urchins move about bya. tentaclesb. flexible armsc. movable spinesd. small pincherse. extruding slime
Most reproduction in echinoderms isa. sexual and externalb. hermaphroditicc. asexual by fragmentationd. parthenogenice. sexual and internal
Which of the following is not descriptive of deuterostomes?a. embryo divides by radial cleavageb. larva is a trochophorec. anus develops from the blastopored. includes echinoderms and chordates
Echinoderms are most closely related to: a. roundworms b. mollusks c. annelids d. arthropods e. chordates
Early embryonic development of echinoderms is similar to that found in a. gastropods b. arthropods c. cephalpods d. humans e. other protostomes
Which of the following is not an echinoderm?a. sea urchinb. sea starc. octopusd. sea cucumber 
Which of the following is not characteristic of the sea stars?a. water vascular systemb. central disk with five or more armsc. notochordd. spiny skeletone. tube feet
The larval stage of a sea stara. Has radial symmetryb. Has pentaradial symmetryc. Has bilateral symmetryd. Is symmetrical
The water vascular system is characteristics of:a. Echinoderms onlyb. Echinoderms and chordatesc. Chordates onlyd. Arthropods only
The water vascular system:a. Is used to distribute water to the tube feetb. Is used to regenerate body partsc. Is used to filter feedd. Is used for reproduction
Which of the following is not an example of an echinoderm?a. Sea starb. Sea lillyc. Sea cucumberd. Sea squirt
In vertebrates the blastopore becomes the anus, and during cleavage, the regulatory signal in the egg are evenly distributed in the cells. An invertebrate phylum sharing these characteristics is the:a. Arthropodab. Nematodac. Annelidad. Molluscae. Echinodermata