Indicate whether the statement is true or false.
____1.The acute senses of arthropods are the result of organs such as compound eyes and antennae.
____2.Arthropods have a well-developed excretory system consisting of nephridia.
____3.The well-developed arthropod nervous system consists of a double ventral nerve cord, an anterior brain, and several ganglia.
____4.Efficient gas exchange in arthropods is accomplished by tracheal tubes, book lungs, or gills.
____5.The exoskeleton is a protective adaptation that enables arthropods to move freely.
____6.Jointed appendages are advantageous because they are limited in their strength and functions.
____7.In arthropods, appendages are adapted for a variety of purposes including sensing, walking, feeding, and mating.
____8.The exoskeleton of arthropods is harder and provides more protection than the cuticle of annelids.
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.
____9.Roundworms are have one body opening. _________________________
____10.All roundworms are parasites. _________________________
____11.Trichinella can be ingested in raw or undercooked pork. _________________________
____12.Pinworms are the most common parasites in children living in the United States. _________________________
____13.Hookworms can be contracted by eating improperly cooked infected pork. _________________________
____14.The most complex and most recently evolved mollusks are gastropods. _________________________
____15.Earthworms are hermaphrodites because each worm produces both eggs and sperm. _________________________
____16.The respiratory organs in aquatic gastropods are primitive lungs. _________________________
____17.Gastropods have two shells. _________________________
____18.The excretory structures in mollusks are called nephridia. _________________________
____19.Bivalves obtain food by predation. _________________________
____20.In shelled mollusks, the radula secretes the shell. _________________________
Identify the choice that best completes the statement or answers the question.
____21.Animals with bilateral symmetry find food and mates and avoid predators more efficiently because they have _____. a.|body cavities|c.|tails|
b.|more muscular control|d.|the ability to see in all directions|
____22.Which of these animals has bilateral symmetry?
____23.What type of symmetry does a penny have?
a.|bilateral symmetry|c.|no symmetry|
b.|radial symmetry|d.|biaxial symmetry|
____24.Which of the following applies to a sponge?
a.|intracellular digestion|c.|bilateral symmetry|
b.|has a gastrula stage|d.|develops three embryonic layers|
____25.The animal's digestive tract forms from the _____.
____26.The embryo layer that forms the skin and nervous tissue is the _____. a.|endoderm|c.|ectoderm|
____27.In Figure 25-2, where is the ectoderm?
____28.In Figure 25-2, where is the endoderm?
____29.In Figure 25-2, where is the mesoderm?
____30.In Figure 25-2, where is the gastrula?
____31.In Figure 25-2, if part A develops into a mouth, this organism will be a _____. a.|protosome|c.|autosome|
____32.Which of the organisms in Figure 25-3 is asymmetrical? a.|A|c.|C|
____33.Which of the organisms in Figure 25-3 probably has the most muscular control? a.|A|c.|C|
____34.Which of the organisms in Figure 25-3 has the most complex systems developed...