Assignment 3 OBJ 4 and 5 Unit 2

Assignment 3 OBJ 4 and 5 Unit 2

Use the textbook and notes to answer the following questions.

Question 1 1 pts

Cnidarians and Ctenophores have this type of body symmetry

spiral

radial

asymmetrical

bilaterial

Question 2 1 pts

A capsule that contains a coiled, threadlike tube. The tube may be sticky or barbed, and it may contain toxic substances. They are located on stinging cells on the tentacles.

gastrovascular cavity

nerve net

nematocyst

polymorphism

Question 3 1 pts

The sessile form of a cnidarian. Its mouth is surrounded by tentacles. Examples include sea anemones and corals.

polyp

larvae

medusa

budding

Question 4 1 pts

the free swimming form of a cnidarian. It possesses an umbrella-shaped, floating body, called a bell, with the mouth on the underside.

larvae

polyp

budding

medusa

Question 5 1 pts

An area inside the cnidarian which has cells adapted for digestion and release enzymes over captured prey. Any undigested materials are ejected back out through the mouth.

gastrovascular cavity

water vascular system

Nerve Net

polymorphism

Question 6 1 pts

A simple nervous system (without a brain), in which impulses to and from all parts of the body are sent. The impulses cause contractions of muscle-like cells in the two cell layers.

nerve net

water vascular system

gastrovascular cavity

nematocyst

Question 7 1 pts

The release of a part of an organism which can develop into another organism.

external budding

sexual reproduction

germ layers

polymorphism

Question 8 1 pts

The presence in a species of more than one structural type of individual. (polyp and medusa).

metamorphosis

polymorphism

cnidocytes

nematocysts

Question 9 1 pts

There are no terrestrial cnidarians (cnidarians which live on land).

True

False

Question 10 1 pts

Cnidarians sometimes live symbiotically with other animals often as commensals on the shell or other surface of their host.

True

False

Question 11 1 pts

Some cnidarians live in fresh water.

True

False

Question 12 1 pts

Cnidarians do not have an excretory or respiratory system.

True

False

Question 13 1 pts

Polyps are typically carnivorous, catching prey with their tentacles and passing them through the mouth into the gastrovascular cavity for digestion.

True

False

Question 14 1 pts

which is the correct sequence of the life cycle of a jellyfish:

1) A polyp grows and buds repeatedly

2) External fertilization takes place in the sea

3) A zygote develops into a blastula, which develops into a larva

4) Male and Female medusae release sperm and eggs, respectively.

5) A cilia-covered larva settles onto a surface.

6) A tiny medusa breaks free from its sessile parents and drifts away.

4,2,5,3,1,6

4,2,3,5,1,6

4,2,6,5,1,3

4,2,3,5,1,6

Question 15 1 pts

What is the mode of reproduction of medusae?

asexual by budding

sexual by budding

sexual by releasing sperm and eggs

asexual by gemmules

Question 16 1 pts

What is the mode of reproduction of polyps?

asexual by gemmules

sexual by budding

asexual by budding

sexual by releasing sperm and eggs

Question 17 1 pts

Where does fertilization of egg cells by sperm cells occur?

around the polyp in the open ocean

below the medusae in the open ocean

inside of the polyp

inside of the medusae

Question 18 1 pts

Polyps reproduce by asexually by budding. The small buds grow as extensions of the polyp's body wall. As the buds develop, they form the mouth and tenacles of tiny polyps, then break away and settle to create a new polyp

True

False

Question 19 1 pts

Polyps reproduce sexually by producing medusae. The medusae then break away from the parent polyp and form into jellyfish.

True

False

Question 20 1 pts

The fertilized egg becomes a zygote, which in turn, grows and develops into a blastula. The blastula becomes a free-swimming larva that must find an area for attachment and the beginning of the asexual phase of the jellyfish life cycle.

True

False

Question 21 1 pts

Both the polyp and medusa have a mouth surrounded by tentacles.

True

False

Question 22 1 pts

The body form of the medusa is tube-shaped and the body form of the polyp is bell shaped.

True

False

Question 23 1 pts

The mouth of the polyp can point upward and the mouth of the medusa is pointed downward.

True

False

Question 24 1 pts

The polyp floats through the water but the medusa is sessile.

True

False