CHAPTER 13: RADIATES (Cnidaria & Ctenophora)

Question 1

cnidocytes

Answer 1

Defensive cells: explosive cell containing one giant secretory organelle called a cnidocyst that can deliver a sting to other organisms.

Question 2

Mesoglea

Answer 2

a gelatinous substance between the endoderm and ectoderm of sponges or cnidarians.

Question 3

planula

Answer 3

a free-swimming coelenterate larva with a flattened, ciliated, solid body.

Question 4

polyp

Answer 4

a sessile, or nonmotile, organism (ex: sea anemone)

Question 5

medusa

Answer 5

when free swimming, is popularly known as a jellyfish.

Question 6

Hydranths

Answer 6

feeding zooids that capture prey

Question 7

Gonangia

Answer 7

– reproductive polyps that form medusa buds

Question 8

perisarc

Answer 8

Hydroid has a non-living chitinous covering

Question 9

velum

Answer 9

shelf-like; a membrane or membranous structure, typically covering another structure or partly obscuring an opening.

Question 10

scyphistoma

Answer 10

the fixed polyp-like stage in the life cycle of a jellyfish, which reproduces asexually by budding (strobilation).

Question 11

ephyrae

Answer 11

buds that break loose to form jellyfish medusae

Question 12

velarium

Answer 12

Increases swimming efficiency

Question 13

protandrous

Answer 13

Produce sperm first and eggs later