Porifera

Question 1

What is Porifera?

Answer 1

Phylum - sponges

Question 2

Spongin

Answer 2

Scleroprotein threads

Ex: structure in bath sponges

Question 3

Amoebocytes

Answer 3

Special cells in sponges

Secrete spicules

Transports food

Question 4

Osculum

Answer 4

Excurrent hole in sponges

Question 5

Ostium

Answer 5

Small incurrent holes in sponges

Question 6

Spongecoel

Answer 6

Large cavity in sponges

Question 7

Choanocytes

Answer 7

Collar cells

Use flagella to pump water in the the sponge

Catches small amounts of food with mucus and cilia

Question 8

Asconoid

Answer 8

Sac-like, simple, choanocytes lining the big spongecoel

Question 9

Syconoid

Answer 9

Choanocytes in individual side chambers

Question 11

Porocytes

Answer 11

Canals in sponges where water enters

Question 12

What is Calcarea?

Answer 12

Class - Sponges

CaCO3 spicules

Asconoid, syconoid, and leuconoid

Question 13

What is Hexactinellida?

Answer 13

Class - sponges

Glass sponges

SiO2 spicules and always have 6-rated cube spicules

Looks most like syconoids

Question 14

Spicules

Answer 14

Tiny “rods” of CaCO3 or SiO2

Wide variety of shapes and sizes

Ex: pitchforks, jacks, shovels

In sponges

Question 15

Sponge Reproduction

Answer 15

Sexual

• choanocytes undergo meiosis to make eggs or sperm
• sperms are released
• eggs -> larvae -> sponge

Asexual

• recognize self vs. non-self
• regeneration

Question 16

What is Demospongiae?

Answer 16

Class - sponges

95% of all species

SiO2 spicules or spongin or both

All leuconoid

Question 17

Reasons for Porifera success?

Answer 17

1. No definite shape
2. Plasticity to environment
   - thick (wave-exposed) vs. thin (wave-protected)
3. Few predators
   - spicules, few nutrients, chemical defense
4. Symbionts
   - hermit crabs, scallop, algae

Question 18

Porifera Ecology

Answer 18

Mainly marine

Almost any hard substrate

Poles to equator

Completely sessile except for larvae

Question 19

Porifera Body Plan

Answer 19

No definite structure

Pores, canals, and flagellated chambers

No true tissue

Question 20

Porifera Skeleton

Answer 20

Spongin and/or spicules

Question 21

Porifera Feeding

Answer 21

Feed on nanoplanktons and organic matter

Use of choanocytes and amoebocytes

Question 22

Porifera Respiration

Answer 22

Diffusion

Question 23

Porifera Sensory Equipment

Answer 23

None

Evidence of signal conduct (choanocytes)

Question 24

Porifera Waste

Answer 24

Diffusion

Question 25

Leuconoid

Answer 25

Choanocytes in many small chambers

The most efficient