Ch 18 workbooks Essay

Submitted By willfrance
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Pages: 17

Lesson 18.1: True or False
Name___________________ Class______________ Date________
Write true if the statement is true or false if the statement is false.
___f__ 1. Sponges are terrestrial invertebrates.
___t__ 2. Adult sponges cannot move from place to place on their own.
___t__ 3. Because sponges evolved before other invertebrates, they do not have a skeleton.
___t__ 4. Bacteria are one food source for sponges.
___f__ 5. The function of a nematocyst is gamete (egg and sperm) production.
___f__ 6. Cnidarians have ectoderm, endoderm, and mesoderm.
___t__ 7. Some Cnindarians have a life cycle in which they alternate between medusa and polyp body forms.
___t__ 8. The planula is the larval form of Cnidarians.
___t__ 9. Corals have a mutualistic relationship with algae.
___t__ 10. Some flatworms are less than an inch long, while others are over 60 feet long.
___f__ 11. Flatworms have a respiratory system.
___t__ 12. Some flatworms are parasitic.
___t__ 13. Roundworms are round because they have psuedocoelom.
___f__ 14. Most roundworms reproduce asexually.
___t__ 15. Pinworms are a type of roundworm.
Lesson 18.1: Critical Reading
Name___________________ Class______________ Date________
Read these passages from the text and answer the questions that follow.
Ecology of Flatworms
Both flukes and tapeworms are parasites with vertebrate hosts, including human hosts. Flukes live in the host’s circulatory system or liver. Tapeworms live in the host’s digestive system. Usually, more than one type of host is required to complete the parasite’s life cycle. Look at the life cycle of the liver fluke in the diagram below. As an adult, the fluke has a vertebrate host. As a larva, it has an invertebrate host. If you follow the life cycle, you can see how each host becomes infected so the fluke can continue its life cycle.

Life Cycle of the Sheep Liver Fluke. The sheep liver fluke has a complicated life cycle with two hosts. How could such a complicated way of life evolve?(Image courtesy of the Centers for Disease Control and Prevention and under the public domain.)
1. What are some major characteristics shared by tapeworms and flukes?
They are parasites and the have vertebrate hosts.
2. Where does the fluke described in the reading above live in humans?
In the circulatory system or liver.
3. What is another host of the liver fluke?
The liver fluke has an invertebrate host as an intermediate.
4. When does the fluke live in this host?
When it is a larvae.

5. How does it get from the human host to this host?
Fecal matter.
Lesson 18.1: Multiple Choice
Name___________________ Class______________ Date________
Circle the letter of the correct choice.
a. Members of the Porifera phylum have
a. no skeleton.
b. an exoskeleton.
c. an endoskeleton.
d. either an exoskeleton or endoskeleton, depending on the species.
b. Sponges reproduce
a. sexually in a way favoring cross-fertilization.
b. sexually in a way favoring self-fertilization.
c. asexually with sperm only.
d. none of the above
c. Sponges can protect themselves against predators by
a. moving away from the predator.
b. making toxins to poison predators.
c. using their muscles.
d. a and b
d. The motile stages of the Cnidarian life cycle include the
a. polyp stage.
b. larval stage.
c. medusa stage.
d. b and c
e. The phylum with endoderm, mesoderm, and ectoderm is
a. Cnidaria.
b. Porifera.
c. Platyhelminthes.
d. all of the above.
f. Liver flukes
a. live in a snail host during part of their life cycle, and in a human during another part of their life cycle.
b. live in invertebrate hosts only.
c. live in vertebrates hosts only.
d. are free-living.
g. Roundworms have
a. a complete digestive system.
b. a psuedocoelom.
c. muscles.
d. all of the above.
h. Pinworm eggs
a. are a type of egg made by flatworms.
b. are made in the soil.
c. are made in the host's digestive tract.
d. are never found in the United States.
Lesson 18.1: Vocabulary I
Name___________________ Class______________ Date________