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Flashcards in Chapter 7 Deck (15)
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1

The ciliated larva if the cnidarians is called a _______

Planula

2

True/False

The freshwater Hydra has a medusa stage in its life cycle

False

3

Nematocysts are expelled when

The internal hydrostatic pressure increases when water enters due to osmotic pressure inside

4

The body wall of a Hydra consists of an outer epidermis and an inner gastrodermis with _________ between them

Mesoglea

5

Digestion in cnidarians is

Both extracellular and intracellular

6

The structure of the nervous system in cnidarians is referred to as a __________

Nerve net

7

True/False

The Anthozoa include the marine sea anemones and corals

True

8

True/False

All ctenophores are marine, and most of them are free-swimming forms

True

9

True/False

The central nervous system of cnidarians includes a brain

False

10

True/False

Cnidarians are widespread in marine habitats, but there are a few freshwater forms

True

11

In cnidarians, extracellular digestion occurs in the

Gastrovascular cavity

12

The class of cnidarians with the most conspicuous medusa stage is

Scyphozoa

13

Molecular evidence suggests that hydrozoans, scyphozoans, and cubozoans shared a common ancestor with an Anthozoan life cycle and a _______ form later to the life cycle

Medusoid

14

A common characteristic of cnidarians is

Dimorphism and often polymorphism

15

True/False

The anthozoans include the marine sea anemones and corals

True