Chapter 33 - Chapter 33 Noncoelomate invertebrates Parazoa...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 33 Noncoelomate invertebrates Parazoa I. Phylum – Porifera (pore bearing) A. Characteristics; 1. asymmetry, some considered radial 2. no tissues or organs 3. specialized cell types 4. filter feeding 5. sessile 6. waste – diffusion of ammonia 7. gas exchange = diffusion B. Cell types 1. pinacocytes – form outer layer of sponge 2. amoebocytes – move around in a jellylike matrix (mesohyle) functions; food storage and transport, skeleton formation, reproduction 3. Choanocytes = (collar cells) unique to phylum flagellated cells that filter bacteria, algae, protists (food vacuole)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
C. Skeleton – used for classification 1. Spicules – needle like spines CaCO 3 SiO 2 2. Spongin – protein fiber (collagen) 3. skeleton = spicules, spongin or both D. Body types (forms) 1. Ascon –most simple body form, spongocoel is lined with choanocytes, single osculum (small) 2. Sycon – folding of the ascon body plan radial canals 3. Leucon – most complex, most common, chambers lined with choanocytes, increased filtering = increased size E. Classes of sponges 1. Calcarea a. CaCO 3 spicules b. All 3 body plans c. All marine 2. Hexactinellida – glass sponges a. SiO 2 spicules, six spined (hex) b. sycon or leucon
Background image of page 2
3. Demospongiae – bath sponges
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/10/2009 for the course BIOLOGY 21909 taught by Professor Jefffeaster during the Spring '09 term at Fullerton College.

Page1 / 9

Chapter 33 - Chapter 33 Noncoelomate invertebrates Parazoa...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online