Biology 102Study Guide Exam #3Invertebrates: have no backbone- Ex. Mimic octopusHow do we define an animal?- Eukaryotes- Multicellular- Heterotrophs- Lack cell walls- Diploid- Short lived gametes by meiosisProkaryotes: cell wall peptidoglycanFungi: cell wall chitinPlants: celluloseAnimals: lack a cell wall- Cephalization- most active animals have sense at head region (anterior)- Radial- there’s no clear head with sensory organismo You cut it any way you get equal halves (from the central axis)- Bilateral- does have a head regiono Anterior: heado Posterior: tailo Most sensory organs are in the headSpongesNo body plan, no symmetry for any of these and no true issue- Sedentary- Suspension feeders (filter feeders) filter water and feed from particles in the water- Sessile: they can’t move or escape from predators Choanocytes: move flagella, trap food with mucousAmeobocytes: distribute food around sponge- Produce skeletal fibers (spongin)- All sponges have sponging, but not all have spiculesBiology 102Spicules: sharp, protective organ, defense mechanismCnidarians- tentacles and singing cells - Outer epidermis and inner cell layer lining- Radial, sedentary animalso Ex. jelly fish- Polyps: they are sedentary- Medusa: they moveTapewormsParasitic flatworms - Inhibit the digestive tracts- gastrovascular cavity of cnidarians (and flatworms) is the functional equivalent of two systems in our bodies, serving as the site of digestion and the method of nutrient delivery.- Flatworms are the simplest bilateral animalsTapewormsTapeworm: parasitic flatworm - Penis fencing: when flatworms fence 2 “males” use their penises to fence one another. The winner or the flatworm that stabs the other with his penis gets to remain male whilethe other becomes female.RoundwormsRoundworms can be free living and or parasitic as well- Trininella larvae: in the muscle of porko It goes into metamorphosis and forms into an adult roundwormGuinea worm: 3.5 million cases in 1986, 1,800 in 2012- Drink infected water with water flea and that water flea has the guinea worm larvaeInsects70% of animal species are insects- Success of animalso Exoskeleton: not living, this is a problem because in order for them to grow they have to molt leaving the insect really vulnerable and unable to moveBiology 102o Waterproof cuticle: allows them to live in hot environments80% of insects undergo metamorphosis- Complete metamorphosis: larval stage that does not resemble the adulto Caterpillar represents larval stage Is specialized for eating and growing Enclosed as a nonfeeding pupa Have embryonic stem cells on reserve  Metamorphosis occurs Emerge as the adult  Adult form: usually lives in a different place  specializes in dispersal and reproductionChordatesChordates: not all chordates are vertebrates- Chordates include vertebrates AND invertebrates- 4 Characteristics:1. Dorsal hollow nerve cord (in vertebrates think of it as a spine)2. Flexible supportive notochord or rod (vertebral column)3. Pharyngeal slits (ex. fish have gills or a human embryo when its developing has slits to help it breathe)- Develop into different structures: gills, auditory cavity, sinus cavity4. Muscular post anal tailAll of these characteristics must occur at a certain point during the life cycle, they can happen atthe same time or at different times, but they all happen.Simple Chordates:- Tunicates: aka sea squirt- Stationary, don’t move, become sedentary and attach to a surface- Invertebrate chordate- First to have a brain- Lancelet: - Closest living non vertebrate relative to vertebrate- Invertebrate chordate- Hagfishes- First to develop a skull- Slime glands- Enters through any opening or attaches to the animalBiology 102- If a fish swallows him he spits slime that fills the gills of the fish so the fish cant breathe and spits him out- Lampreys- Attach themselves to things - Oral discs as mouths ChondricthayansBest examples of chondricthayans are sharks and sting raysProperties:- A cartilage skeleton- Most chondricthayans are predators. The soft skeleton allows them to swim fast- Keen sense of smell- Sharp vision- Electro sensors on head that detect minute electrical fields- Their bodies are adapted for life on the bottom of the ocean (flat)Ray FinnedRay finned fish also known as bony fishProperties:- Flattened scales covered with mucous reduces drag while swimming, makes it easier to swim- Operculum (flaps on the side of the head covering the gills)- Swim bladder (gas filled sac): it inflates and deflates with gas in order to move up or down in the water; buoyancyLobe FinnedProperties:- Muscular fins, very thick stout bones- Homologous to bones in amphibians3 Lineages:- Lung fisheso Can go to the surface of the water and breathe air- Tetrapodso Live in still water- CoelacanthsBiology 102Amphibians were the first vertebrates to make it to landAmphibiansAmphibians: are tetrapods (four limbs)- First tetrapods to move on land- They live a double life part of it in water some on lando Lay their jelly like eggs in water and live their adult life on landReptilesReptiles: do not require moisture- Amniotes: tetrapod with a terrestrially adapted eggo Amniotic egg with an amnion, a private pond in which the embryo develops- Nonbird reptile are ectothermic (regulate temperature by seeking shade)Reptiles other than birds are ectotherms (aka coldblooded)- Cold blooded- not really a good description- Environment regulates body temperature- Range restricted- Not active if cold (if they are cold they literally cannot move)- Less energy required, less food requiredEndothermsEndotherms aka warm blooded - They use their metabolism- Metabolism regulates temperature- More of an energy requirement more rangeo Ex. birdsBirds from lineage of a small dinosaur therapod- Long tail with many vertebrae, feathers, wing claw, teeth like dinosaur- Adaptations:o Loss of teetho Tail supported by only small vertebraeo Feathers with hollow shafts- Flight is very costly and birds are endotherms with a high rate metabolismo Need strong breast boneso Have large brains, strong senses needed to surviveBiology 102Monotreme- egg laying mammal- Oldest groupo Duck billed