which of the following distinguishes sponges from other invertebrates

a. arent motile in any stage of life cycle

b. obtain nutrients by diffusion rather than ingestion

c. cells arent organized into tissues

d. reproduce only asexually

sponges

a. are nonsymmetrical

b. lack organization into tissues and organs

c. possess cells that are capable of recognizing other sponge cells

d. all of the above

collar cells

a. are specialized for reproduction

b. draw water into the body of a sponge

c. produce cytochrome oxidase

d. are parasitic protozoa

spicules are

a. flexible protein fibers

b. hard spike- like structures in the wall of a sponge

c. similar to seeds; a complete sponge can grow from each spicule

d. used for taking in food and water

adult sponges

a. have body walls with many pores

b. possess true tissues

c. are active swimmers

d. use stinging cells to capture prey

skeletal support in sponges may be provided by

a. spicules of calcium carbonate

b. spicules of silicon dioxide

c. fibers called spongin

d. all of the above

sponges obtain food

a. through photosynthesis

b. by using their spicules to paralyze protozoa

c. by filtering small organisms from the water

d. with their spongin

in sponges, currents that draw water through the organism are created by

a. amoebocytes

b. collar cells

c. gemmules

d. spicules

the cells that move throughout the sponge's body wall to deliver food to the organism's cells are called

a. amoebocytes

b. choanocytes

c. gemmules

d. spicules

water leaves the interior of a sponge through the

a. food vacuoles

b. spicules

c. body wall

d. osculum

collar cell: water::

a. amoebocyte: nutrients and wastes

b. spongin: food

c. spicule: water

d. osculum: mesenchyme

the gemmules of sponges

a. create water currents for feeding

b. are equivalent to the sperm cells of higher animals

c. are equivalent to the egg cells of higher animals

d. are necessary for one form of asexual reproduction

hermaphroditic organisms

a. reproduce only by asexual means

b. produce both eggs and sperm

c. have gemmules that are fertilized by amoebocytes

d. possess only male amoebocytes

hermaphrodism is advantageous in sponges because

a. they reproduce asexually

b. they have gemmules

c. they are sessile

d. none of the above, sponges aren't hermaphroditic

sponges can reproduce

a. by the budding of new sponges from the parent

b. by a breakup of the original parent into fragments that become a new sponge

c. sexually using sperm and eggs

d. all of the above

some freshwater sponges: gemmules::

a. hermaphrodites: eggs and sperm

b. gemmules: eggs

c. gemmules: sperms

d. amoebocytes: eggs

many cnidarians have two distinct life stages

a. gametophyte and sporophyte

b. polyp and medusa

c. egg and adult

d. egg and larva

nematocysts

a. contain harpoonlike structures called cnidocytes

b. create water currents in sponges

c. can spear cnidarians prey

d. are found in most predatory ctenophores

the cnidarian's inner layer of tissue is specialized for

a. digestion

b. reproduction

c. capturing prey

d. all of the above

the outer cell layer of a cnidarian is the

a. ectoderm

b. mesoglea

c. endoderm

d. epidermis

which of the following characteristics is only associated with cnidarians

a. digestive tract with single opening

b. cnidocytes specialized for defense and capturing prey

c. choanocytes containing nematocysts

d. parasitic life cycle

sponges: fewer than three body layers::

a. ctenophores: no body symmetry

b. sponges: bilateral symmetry

c. cnidarians: nerve net

d. cnidarians: choanocytes

the phylum cnidaria includes all of the following except

a. jellyfish

b. squids

c. sea anenomes

d. corals

planula larvae of scyphozoans

a. result from fertilization of eggs by sperm

b. swim freely through water

c. settle to the ocean bottom and grow into polyps

d. all of the above

the hydra is unique among the hydrozoans because it

a. is an active swimmer

b. lives in colonies

c. is strictly a marine species

d. has no medusa stage

which of the following isn't sessile as an adult

a. sponge

b. coral

c. sea anenome

d. portugese man of war

sea anenomes are

a. medusae

b. polyps

c. larvae

d. eggs

anthozoans include

a. jellyfish

b. hydras

c. portugese man of war

d. sea anenomes and corals

schyphozoans, such as jellyfish, spend most of their lives as

a. polyps

b. medusae

c. corals

d. parasites

class of cnidarians that typically live only as polyps is

a. anthozoa

b. hydrozoa

c. scyphozoa

d. none of the above

which of the following isnt a characteristic of ctenophores

a. bioluminesence

b. movement by means of beating cilia

c. use of cnidocytes to capture prey

d. hermaphrodism

food filled balls of amoebocytes that are involed in asexual reproduction in sponges are called