Invertebrates

Invertebrates - 3/8/10 Invertebrates Chapter 33 Most Recent...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 3/8/10 Invertebrates Chapter 33 Most Recent Hypothesis About Animal Phylogeny - Figure 32.11 Concept 33.1: Sponges are basal animals that lack true tissues • Porifera: Phyla Calcarea & Silicea - Live in b o t h fr e s h a n d m a ri n e w a t e r s - Lack tr u e tis s u e s a n d or g a n s - Asy m m e t ric al b o d y Spong es • S p o n g e s a r e s u s p e n sio n fe e d e r s Filt er w a t e r p a s si n g t hr o u g h t h eir b o di e s Co nc e p t 3 3. 2: Cnid a ri a n s a r e a n a n ci e n t p h yl u m of e u m e t a z o a n s Cnid a ri a n s • • A wid e r a n c e of s e s sil e a n d flo a tin g for m s inclu din g jellyfis h, c or al s, a n d h y d r a s Si m pl e iploblastic, radial body plan d Sin gl e o p e ni n g s e r v e s a s b o t h m o u t h a n d a n u s Me s o gl e a lay e r b e t w e e n e pi d e r mi s a n d e n d o d e r mi s ( g a s tr o d e r mi s) Cnid a ri a n Body Pla n s • Polyp for m is g e n e r ally s e s sil e • Me d u s a for m m o v e s fr e ely in w a t e r b y p a s siv e d riftin g a n d c o n tr a c tio n s of t h e b ell D efinin g Fe a t ur e of Cnid a ri a n s • Cnido cy t e s - Uniq u e t h a t fun c tio n in d ef e n s e a n d t h e c a p t ur e of pr e y • Sti m ul u s c a u s e s t h e c ell t o e v e r t r el e a si n g t hr e a d • So m e c nid oc yt e s s tin g, o t h e r s ju s t e n t a n gl e pr e y Cnid a ri a n Div er sity • Hydr oz o a • Scy p h oz o a(j ellyfis h) • Cu b oz o a • Ant h oz o a( s e a e m n e mi n e ) Co nc e p t 3 3. 3: Lop h o troc h oz o a n s , a cl a d e id e n tifie d b y m ol e c ul a r d a t a , h a v e t h e wid e s t r a n g e of a b o d y for m s - Figur e 3 3. 2 Fla t wor m s • • Phylu m Pl a t y h el mi n t h e s Triplobl a s tic d e v elo p m e n t, b u t a c o el e o m a t e Class Turbellaria Have - Light­sensitive eyespots - Centralized ner ve net w/ anterior ganglia - Gastrovascular cavity w/ 2­way phar ynx Class Trematoda ­Blood fluke, Schistosoma mansoni, life cycle ­ Figure 33.11 Tapeworms • • • • Class Cestoda Scolex attaches to the host Proglottids are the reproductive structures Break off after fertilization ...
View Full Document

Ask a homework question - tutors are online