Animals (Bio 212) Practice Questions with Correct Answers

Tissues group of cells with a common structure and/or function collagen protein only in animals used for support instead of cell wall how do animals obtain nutrients heterotrophs but have to ingest food and digest it inside the body traits that make animals unique o Do not have cell walls, but have matric of collagen o Multicellular eukaryotes that ingest and digest prey within bodies o 2 types of cells not found in other organisms: muscle and nervous o Directed movement is central to animal lifestyle and how they obtain food what organism is the evolutionary ancestor of animals, and what evidence do we have for this relationship o Suspension-feeder similar to living protists known as choanoflagellates o Choanoflagellates are identical to "collar cells" in sponges, which is the basal group of animals what phylum is the basal group of animals porifera what are the characteristics of phylum porifera (sponges), and in what ways are organisms in this phylum simpler than other animals o Sedentary; mistaken for plants by ancient Greeks o Filter feeders with more complex arrangement of same basic components as colonial choanoflagellate o Use collar cells to capture food from water drawn in through pores o Range in size from few mm to few meters o 2 layers of cells separated by jelly matrix called mesohyl o Only animals that are asymmetric and lack true tissues radial symmetry divided into many equal parts bilateral symmetry divided into 2 halves cephalization sensory organs and nervous tissue in head coelomate mesodermic body cavity Pseudocoelomate both mesodermic and endodermic tissue