Animals Have: A. Heterotrophic lifestyle a. Feeding from another animal rather than from themselves B. Flexible cell membranes a. Create extra cellular matrix (ECM) i. Exuded from the cell ii. Ex: Osteoblasts and puss- all exude things to help the body iii. Not all animals do this C. Glycogen a. All the nutrients broken down into glycogen b. Can be used as an energy source or stored for later D. Neuromuscular tissue a. Ability to move in larval stage E. No alternation of generations a. In attached animals, both forms are multicellular diploid i. Unlike in plants where gamete producing form is haploid b. Unknown reason Protist ancestors of Animalia A. Choanoflagellate protists a. Closest living relative of the animals B. Phylum porifera a. Most ancient animal phylum w living representatives b. Similarity b/w feeding cell members of the choanoflagellate and choanocyte cells of sponges c. Choanocyte cells: cells with an attached cylinder of microfibrils within which a flagellum resides C. Micro feeders a. Flagellated collar cells = phylogenetic connection b/w protists and animals i. Supports belief that specialized cells evolved when only the smallest suspended organisms were available as food b. No animals other than sponges able to capture such small food items Fundamental traits of animal groups A. Germ layers a. Layers of similar dividing cells (like plant meristematic cells) i. Each layer produces a characteristic subset of structures in the animal b. Animals without germ layers i. Diff looking cells come together and functioni as a multicellular 1. Cells remain totipotent ii. Ex: a sponge1. It can rearrange itself, be separated and put itself back together again a. It has identical cells but each cell take on diff roles based on where they are- totipotent c. Diploblastic: 2 germ layers of creation i. Ectoderm: creates all the outside skin and nervous system ii. Endoderm: creates lining of digestive tract d. Triploblastic i. Endoderm: ii. Ectoderm iii. Mesoderm: in the center 1. Constitutes most of the animals 2. Creates bones, muscles, B. Body symmetry a. Asymmetry i. Ex: sponges Odd little pouches here and there b. Radial symmetry i. Circular body with equally effective action/response in all directions 1. Ex jellyfish c. Bilateral symmetry i. Only 1 plane of symmetry ii. Ex; human heart a little off center, liver a little bigger on one side but symmetrical on the outside iii. Most animals are bilateral C. Body Cavity (triploblasts only) a. Those with mesoderm, Separates internal organs from the body wall >> maneuver b. Like a garden hose c. Eucoelomate: i. Mesoderm creates everything inside the body cavity ii. Circle looking. structure d. Acoelomate i. No mesoderm- body cavity ii. Flat oval looking iii. No space to carry nutrients iv. Ex: flatworms e. Pseudocoelomate i. All organs inside the body cavity aren’t covered by the lining 1. The diff between this and eucoelomate ii. Continually bathed in their body fluidiii. At risk of damage whenever move bc nothing protected iv. More efficient transfer nutrients v. Ex: nematodes D. Embryology a. Blastosphere: helps to distinguish phyla bc of what they become b. Protostome: blastopore folds in and becomes a mouth c. Deuterostome: blastopore becomes anus Classification of major animal groups A. No germ layers a. Phylum: porifera: Sponges b. Represent dead end phylum c. Evolutionary speaking doesn’t lead to anything else even though very primitive B. Diploblasts a. Phylum: cnidaria b. Ex: coral, anemones, jelly fish c. sessile/ slow moving hunters with paralyzing harpoons d. Gastrovascular cavity extending to most of body tissue deliver nutrients e. Inside the cell Nematocyst C. Lophotrochozoans protostomes a. Triploblastic animals w i. bilateral symmetry, ii. blastopore becoming mouth iii. Showing incremental additions to the body b. Phylum: platyhelminthes (flatworms and parasitic flukes and tapeworms) i. Most primitive groups: ii. bilateral symmetry, cephalization, tube in tube iii. Grow by adding segments to their bodies as they grow older iv. Acoelomate: no body to cavity so it must be flat and have high surface area c. Phylum: Annelida: segmented worms i. Leeches, earthworms, predatory marine worms ii. Hydrostatic (liquid inflated) skeleton and Gripping setae 1. Assist in burrowing through substrate iii. All internal organs surrounded by mesoderm iv. Bilateral sym, Ectoderm d. Phylum: Mollusca: (chitons, snails, clams, squid, octopus) i. 2nd largest phylum and very diverse ii. Likely evolved from annelid ancestor iii. Evolved mantel: shelliv. Bilateral, eucoelomate v. Moves water inside to move D. Ecdysozoans protostomes: triploblastic animals w bilateral symmetry, blastopore becoming a mouth, showing growth via repeated shedding of exoskeleton a. Phylum Nematoda: nematodes or roundworms i. Endysis: Shedding and growth spurts ii. Thick cuticle protect entire enut iii. Bilaterally symmetrical iv. Triploblastic v. Pseudocoelomate vi. Nematodes active role in nutrient cycling vii. Most abundant multicellular organism that feeds on bacteria and fungi viii. Cause diseases in animals: trichinosis, elephantiasis ix. No mesodermal lining 1. All bare organs = organs constant bathing in nutrients a. Don't’ need to be transported by anything 2. But damage b. Phylum: Arthropoda: insects, crustaceans, spiders, ticks, scorpions i. Largest phylum (most numerous) ii. Evolved from annelid ancestor iii. Segmentally arranged appendages/bodies iv. Chitinous external skeleton evolved >> move out of water to land v. Mollusks heavy shells vi. Marine worms segmented for flexibility but not speedy on land vii. Exoskeleton: strong, economical, speedy viii. Later evolved tracheae system and compound eye (spot food not bump) ix. Bilateral, triploblastic, eucoelomate x. Tracheae: billowing effect drawing in air and blowing air 1. Able to fly = high metabolism and ability to move air xi. Compound eye E. Deuterostomes: second mouth developed during embryotic growth a. Triplo, eucolom bilateral b. Phylum: echinodermata: Sea urchin, sea stars i. Closest nonchordate relatives we have ii. Slow moving, omni directional, heterotrophs, spine = protection iii. Arm suction for moving and predation c. Phylum: chordata notochord or more i. More mobile, more rigid bodied, ii. inc cephalizationiii. 4 key chordate characteristics 1. Notochord: a. support rod along back appearing in early develop 2.