September 18, 2017 Review of Intro To animals BIOL 211 SI September 18, 2017 Review of Intro To animals

Animals 3 characteristics: Multicellular, eukaryotic, no cell wall An animals body plan can range from small (few cell types ex: sponge) to large (tissues and organs ex: vertebrates) 3 different types of skeletal systems: hydrostatic, exoskeleton, endoskeleton All animals (besides sponges) have neurons and muscle cells

Germ Layers Diploblast vs Triploblast Diploblast has 2 germ layers: ectoderm and endoderm Triploblast has 3 germ layers: ectoderm, mesoderm, and endoderm Ectoderm – skin and nervous system derived from ectoderm Mesoderm – both muscle and bone is derived from mesoderm Endoderm – digestive tract and associated organs derived from endoderm

Importance of Animals to Human Welfare Humans depend on animals for food Medical science (painkiller derived from toxin of tropical cone snail, model organisms in medical research.) Animals maintain ecosystem services (plant pollination) Animals adversely affect human health (and economies) (rodents harbor human pathogens.)

Historical Trends Paleozoic era – explosive adaptive radiation during Cambrian period Mesozoic era – ended with dinosaur extinction Cenozoic era – emergence of homo sapiens

Review Question #1 Which of the following statements accurately describes typical observed effects of climate change on coral populations, and mechanisms for these effects. A. Climate change has generally caused increases in coral abundance because coral production increases as water temperatures increase. B. Climate change has generally caused increases in coral abundance because coral production increases as pH of the water declines. * C. Climate change has generally caused declines in coral abundance because coral production declines as pH of the water declines. D. Climate change has generally caused declines in coral abundance because sea levels (nearshore water depth) are declining and coral habitat area is reduced.

Review Question #2 Which of the following lists of traits accurately describes the correct sequence of events of evolution, beginning with the first (earliest or oldest) trait to emerge, and ending with the most recent trait to emerge? A. Body segmentation, diploblast embryo, triploblast embryo, multicellularity, specialized cells, cephalization * B. Multicellularity, specialized cells, diploblast embryo, triploblast embryo, cephalization, body segmentation C. Diploblast embryo, specialized cell, triploblast embryo, cephalization, body segmentation, multicellularity D. Triploblast embryo, multicellularity, cephalization, diploblast embryo, body segmentation, specialized cells

Review Question #3 What is the oldest animal lineage? * A. Porifera (sponges) B. Cnidaria (jellyfish, corals, sea anemones) C. Platyhelminthes (flatworms) D. Mollusca (snails, clams, squid)