The Parazoa

Question 0

What is the phylum within parazoa?

Answer 0

Porifera

Question 1

Name 3 synapamorphies of parazoa

Answer 1

You could have:
Colonial unicellular Protozoa
Filter feeders
No true tissues
Mesohyl cells

Question 2

What are the 3 grades of sponge complexity?

Answer 2

Asconoid
Syconoid
Leuconoid

Question 3

How do they control the rate of pumping water?

Answer 3

By closing the osculum and Ostia. The current is produced by choanocyte flagella.

Question 4

What type of skeletons can they have?

Answer 4

Mesohylar endoskeleton
Spicules either siliceous or calcareous
Spongin

Question 5

How do the parazoa move?

Answer 5

They move from the collective amoeba like movement of skin cells

Question 6

What are dynamic cells?

Answer 6

they are in constant motion, this is due to the lack of intercellular junctions, basal lamina and hemidesmosomes.

Question 7

How do parazoa feed themselves?

Answer 7

Autotrophic or carnivorous

Question 8

How do parazoa defend themselves?

Answer 8

The majority are poisonous, some compete chemically.

Question 9

What are the three methods of clinal reproduction?

Answer 9

Fragmentation
Budding
Gemmules

Question 10

How do parazoa sexually reproduce?

Answer 10

They lack gonads, so the sperm and eggs occur throughout the mesophyll. The sperm arise from choanocytes and the eggs arise from archeocytes. The sperm is captured by the choanocyte which becomes amoeboid and transports to the egg.