Modern Biology Study Guide PORIFERA VOCA (1)

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P

O R I F E R A

VOCABULARY REVIEW

Define the following terms.

1. _choanocyte

2. _osculum

3. _spicule

4. _amoebocyte

MULTIPLE CHOICE

Write the correct letter in the blank.

1. _{Invertebrates are animals that lack}

a.

_{true tissues.}

b.

_{true organs.}

c.

_{a skeleton.}

d.

_{a backbone.}

2. _{Adult sponges are sessile, which means that they}

a.

_{have no gastrula stage.}

b.

_{attach to a surface and do not move.}

3. _{Choanocytes perform all of the following functions except}

a.

_{pumping water into the interior of the sponge.}

b.

_{engulfing and digesting food that is filtered from the water.}

c.

_{passing nutrients to amebocytes.}

d.

_{distributing nutrients throughout the rest of the body.}

4. _{Sponges eliminate carbon dioxide and cellular wastes by}

a.

_{allowing them to diffuse into the water that passes through the sponge.}

b.

_{excreting them into the surrounding water through pores in the body wall.}

c.

_{transporting them to an excretory organ that empties into the osculum.}

d.

_{converting them into usable carbohydrates.}

5. _{After a sponge egg is fertilized, it develops into a(n)}

a.

_{external bud.}

b.

_gemmule.

c.

_larva.

d.

_gastrula.

c.

_{use a jellylike substance for body support.}

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SHORT ANSWER

Answer the questions in the space provided.

1. _{On what basis are animals placed into the invertebrate category?}

2. _{What are the two substances that a sponge’s skeleton may be made of?}

How do these substances differ?

3. _{How do choanocytes participate in the sexual reproduction of sponges?}

4. _{Why is hermaphroditism beneficial in sponges even though they rarely self-fertilize?}

5. _{Critical Thinking}

_{Would gemmules or larvae be better at distributing a population of sponges}

through an area? Explain your reasoning.

STRUCTURES AND FUNCTIONS

Identify the structures labeled

a–e

_{in the diagram of a}

sponge shown below.

184 Section 33-1 Review

Name Class Date

a

b

c

d

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C

N I DA R I A A N D

C

T E NO P H O R A

VOCABULARY REVIEW

Distinguish between the terms in each of the following pairs

of terms.

1. _{polyp, medusa}

2. _{epidermis, gastrodermis}

3. _{mesoglea, planula}

4. _{cnidocyte, nematocyst}

5. _{colloblast, apical organ}

MULTIPLE CHOICE

Write the correct letter in the blank.

1. _{Cnidarians and ctenophores are more complex than sponges because, unlike sponges,}

they have

a.

_{tissues and organs.}

b.

_{both asexual and sexual reproduction.}

2. _{The structure that coordinates the complex activities of a cnidarian’s body is the}

a.

_{gastrovascular cavity.}

b.

_colloblast.

3. _{An example of a cnidarian in the class Hydrozoa is a}

a.

_coral.

b.

_{sea anemone.}

4. _{Corals exist in a symbiotic relationship with}

a.

_fungi.

b.

_algae.

c.

_hydras.

d.

_mosses.

5. _{Ctenophores move through the water by}

a.

_{somersaulting.}

b.

_{contracting their bell-shaped bodies.}

c.

_{beating their cilia.}

d.

_{rotating like a propeller.}

c.

_jellyfish.

d.

_{Portuguese man-of-war.}

c.

_{nerve net.}

d.

_tentacle.

c.

_{a skeleton.}

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SHORT ANSWER

Answer the questions in the space provided.

1. _{How are nematocysts adapted for capturing prey?}

2. _{List three differences between hydras and most other hydrozoans.}

3. _{What is the dominant body form in the life cycle of a scyphozoan?}

What is the dominant body form in the life cycle of an anthozoan?

4. _{Describe two examples of symbiosis found among cnidarians.}

5. _{How do coral polyps produce a coral reef?}

6. _{Critical Thinking}

_{Would you expect to find green hydras in a cave pond that receives little or}

no light? Explain your reasoning.

STRUCTURES AND FUNCTIONS

Identify the structures labeled

a–f

_{in the diagram of a}

cnidarian body shown below.

Which body form is represented by this diagram?

186 Section 33-2 Review

Name Class Date

a

b

c

d

f

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nucleus would contain more than two sets of chro-mosomes. Normal mitosis could not occur, and the zygote would fail to develop normally.

STRUCTURES AND FUNCTIONS

a, protostome; b, deuterostome; c, schizocoely; d, enterocoely; e, mouth; f, anus

Section 33-1

VOCABULARY REVIEW

1. _{A choanocyte is a type of flagellated cell that lines} the interior of a sponge and draws water into the sponge.

2. _{The osculum is the opening at the top of a sponge} where water exits the sponge.

3. _{A spicule is a tiny, hard particle of calcium} carbon-ate or silicon dioxide that makes up the skeleton of some sponges.

4. _{An amoebocyte is a type of cell that crawls about} within the body wall of a sponge and aids in feeding and reproduction.

MULTIPLE CHOICE

1. _d 2. _b 3. _d 4. _a 5. _c

SHORT ANSWER

1. _{Invertebrates are defined solely on the basis of} what they lack—a backbone—rather than on the basis of characteristics they share.

2. _{A sponge’s skeleton may be made of spongin or} spicules (or both). Spongin is a network of protein fibers, while spicules are tiny, hard particles made of calcium carbonate or silicon dioxide.

3. _{Choanocytes engulf sperm and transfer them to} amoebocytes, which carry the sperm to an egg. 4. _{Since all hermaphrodites produce eggs, the chances}

of successful fertilization are greater than they would be if only half the population produced eggs. 5. _{Larvae would be better, since their flagella enable}

them to swim away from the parent sponge and produce another sponge in a new location.

a, osculum; b, amoebocyte; c, choanocyte; d, ostium; e, spicules

Section 33-2

1. _{A polyp is the vase-shaped form of a cnidarian; a} medusa is the bell-shaped form of a cnidarian. 2. _{The epidermis is the outer cell layer of a}

cnidari-an; the gastrodermis is the inner cell layer. 3. _{Mesoglea is a jellylike material between the}

epi-dermis and gastroepi-dermis in a cnidarian; a planula is the ciliated larva of some cnidarians.

4. _{A cnidocyte is a specialized cnidarian cell used for} defense and capturing prey; a nematocyst is an organelle inside a cnidocyte that contains a long, coiled filament.

5. _{A colloblast is a cell found in ctenophores that} secretes a sticky substance to bind prey; an apical organ is a sensory structure at one end of a ctenophore’s body.

Some nematocysts have filaments with sharp tips and spines that can puncture prey and inject poison; others have filaments that can wrap around prey. 2. _{Hydras exist only as polyps, are not colonial, and}

live in fresh water.

3. _{The medusa is the dominant body form in the life} cycle of a scyphozoan. The polyp is the dominant body form in the life cycle of an anthozoan. 4. _{The clownfish live among sea anemones. The}

anemones’ stinging tentacles protect the clownfish from predators, and the clownfish drives away other fish that try to feed on the anemone. Algae live inside corals. The corals supply algae with nutrients, and the algae supply the corals with oxygen. 5. _{Each polyp cements its skeleton to the skeletons of}

adjoining polyps in the colony. When the polyps die, their skeletons remain, and build up into a reef. 6. _{No; the hydras are green because they contain}

algae, which require light to carry out photo-synthesis.

a, epidermis; b, mesoglea; c, gastrovascular cavity; d, gastrodermis; e, tentacle; f, mouth; the medusa

Section 34-1

1. _{A proglottid is a body section of a tapeworm and} contains male and female reproductive structures; a tegument is a continuous sheet of fused cells that covers the external surface of a fluke.

2. _{Cerebral ganglia are clusters of nerve cells that} serve as a brain; eyespots are cup-shaped structures that sense light.

3. _{A primary host is a host from which an adult} para-site derives its nourishment and in which sexual reproduction occurs; an intermediate host is a host from which the larvae of a parasite derive their nourishment.

MULTIPLE CHOICE

1. _c 2. _b 3. _d 4. _a 5. _d

SHORT ANSWER

1. _{Flame cells collect excess water, which is then} trans-ported through excretory tubules and excreted from numerous pores scattered over the body surface. 2. _{Planarians detect the intensity and direction of}

light with two eyespots; tapeworms cannot detect light.

3. _{The primary host is a human; the intermediate} host is a snail. The fluke enters its primary host as a tailed larva that penetrates the host’s skin. 4. _{the larval stage}

5. _{The eggs sometimes block blood vessels, causing} a disease that may kill the host. A parasite that kills its host may not be perfectly adapted to its environment.