Cnidaria

Question 1

What creates are in the cnidaria phylum?

Answer 1

Jellysofh and corals

Question 2

How many species?

Answer 2

10 000

Question 3

What symmetry do they display?

Answer 3

Radial

Question 4

Diplo or triplo blastic?

Answer 4

Diplo

Question 5

What are the common features?

Answer 5

Simple form, mouth =anus, No brain but simple NS

contractile bundles of microtubules act like muscles

Question 6

What are the two forms?

Answer 6

Medusa - mouth down and Polyp

Question 7

What clade do they belong to?

Answer 7

Eumetozoa

Question 8

What is the basic body plan?

Answer 8

Central gastrovascular cavity, single opening

Question 9

What mode of life in polyps?

Answer 9

Sessile, adhere to substrate by aboral end

Question 10

What mode of life in medusa?

Answer 10

Motile, moves by drifting and contraction

Question 11

How do they feed?

Answer 11

Carnivores, use tentacles and mouth to catch prey

Question 12

What are cnydocytes?

Answer 12

Cells unique to cnidarians that function in prey capture - contain cnidae, capsule like organelles that are capable of exploding out

Question 13

What are nematocysts?

Answer 13

Specialised cnidae that contain stinging thread to paralyse

Question 14

What are the 4 classes?

Answer 14

Hydrozoans, scyphozoans, cubozoans, anthozoans

Question 15

Describe the Hydrozoans

Answer 15

alternate between forms, some found in freshwater, reproduce sexually and asexually, very diverse group

Question 16

Describe the Scyphozoans

Answer 16

medusa generally dominant - known as true jellyfish, some go through stage as small polyps

Question 17

Describe the Cubozoans

Answer 17

box shaped medusa stage. complex eyes embedded in the fringe, compositely strong swimmers, highly toxic

Question 18

Describe the anthozoans

Answer 18

Anenomes and corals, occur as polyps, solitary or colonial, may secret carbonate skeleton