BIOL 142 Chapter 32 Study Guide for TEST 3-1

BIOL 142 Chapter 32 Study Guide for TEST 3-1 - Terms used...

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

View Full Document Right Arrow Icon
BIOL 142: Study Guide for TEST # 4 Chapter 32 – Animal Diversity Over 1 million animals in ~36 phyla; diverse group traditionally classified based on anatomy and embryological development General features of animals : multicellular , heterotrophs , specialized cells form tissues (except in sponges), no cell walls, locomotion, sexual reproduction, shared pattern of early embryo development ( zygote morula blastula gastrula ) 5 key innovations leading to major transitions in animal evolution: 1) evolution of tissues ( endoderm digestive tract, mesoderm muscles/skeleton if present, ectoderm epithelium) 2) evolution of symmetry ( radial or bilateral ) 3) evolution of a body cavity ( acoelomate , pseudocoelomate , coelomate ) 4) evolution of different patterns of development ( protostome vs deuterostome ) 5) evolution of segmentation (evolved several different times in different groups)
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Terms used for Classification of Animals: Parazoa – no tissues/no symmetry (= sponges) Eumetazoa – tissues and symmetry (= everything else) Diploblasts- radial symmetry and only 2 tissue layers (= jellyfish) Triploblasts- all 3 tissue layers (= everything else) Protostomes- mouth develops first from blastopore , spiral cleavage, determinate development (= worms, arthropods, mollusks, etc.) Deuterostomes – anus develops from blastopore, radial cleavage, indeterminate development (= echinoderms and chordates) Evolution of Animals : Common ancestor = colonial flagellated protists; explosion of diversity in the Cambrian period (starting about 543 MYA) with NO significant new innovations in major body plans since...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online