BY 124 1st Edition Lecture 9 Outline of Last Lecture Chapter 31 I II Basidiomycetes Deuteromycetes Chapter 32 I II III IV V VI VII VIII Kingdom Animalia Early Embryonic Development in Animals Choanoflagellates are closely related to animals Cambrian Explosion Tree of Life Symmetry Body Cavities and Germ Layers Protostome vs Deuterostome Development Chapter 33 I Kingdom Porifera Outline of Current Lecture Chapter 33 I II III IV V VI Kingdom Porifera Phylum Cnidaria Phylum Ctenophera Acoelomates a Phylum Platyhelminthes Pseudoacoelomates a Phylum Rotifera b Phylum Nematoda Coelomates a Phylum Nemertea Current Lecture Chapter 33 cont These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute I II Kingdom Porifera to bear pores a Sponges all are aquatic b Have a sac structure c No radial symmetry d Used to be thought of as plants e Multicellular like all animals but do not form tissues f Do not gastrulate like other animals i Have epidermis g Choanocytes collar cells living inside Figure 33 4 h Osculum opening i Brings water into spores traps food in flagella digest inside choanocyte and then passes it over to amoebocyte INTRAcellular digestion i No circulatory system ii No digestive system j filter or suspension feeder k Classified by spicules i Calcium carbonate silica collagen like protein l No nervous system m Not extinct due to the fact that they release toxins when damaged or eaten n Reproduce asexually through budding o Usually sponges are hermaphrodites i Make sperm AND eggs in same creature p When water is taken in for food as stated above sperm comes in as well sperm is released into the surrounding water of sponges and the sperm can then fertilize the egg that is retained within the sponge Phylum Cnidaria Figure 33 5 a Alternation in life cycles between two different forms i Alternate between polyp and medusa 1 Can have a dominant form b Radial symmetry therefore won t really move much i Polyp doesn t move much 1 Mouth is up ii Medusa moves more than polyp 1 Mouth is down c Have gastrovascular GV cavity i Where it digests things ii Secretes GV enzymes 1 EXTRAcellular digestion a Slows for the consumption of larger things d Structure Figure 33 6 i Cnidocytes fill tentacles 1 When touched sends signals and then releases threads into in direction of threat III IV e Hydrostatic skeleton f Classes of Cnidaria Figure 33 7 i Class Hydrozoa Ex Obelia 1 Mostly marine but some are freshwater 2 Polyp stage is often colonial 3 Life Cycle of Obelia Figure 33 8 a Bunch of polyps diploid 2 types feeding and reproductive b Medusa bud buds off finds another medusa to mate with to create diversity This produces a zygote The zygote grows into a larva which will form a polyp The polyp will settle somewhere and will develop a colony at which point the process starts all over again ii Class Scyphozoa 1 All marine 2 Polyp stage is reduced absent 3 Free swimming 4 Medusa can get up to 2m big iii Class Cubozoa Ex Box jellies sea wasps 1 All marine 2 Box shaped medusa 3 Potent venom 4 Complex eyes iv Class Anthozoa Ex Sea anemones corals 1 All marine 2 Medusa stage is completely absent 3 Most sessile 4 Many colonial 5 Sometimes forms symbiotic relationship with algae 6 Maintain diversity by sperm and egg Phylum Ctenophera comb jelly a Fluorescent luminescent b Can t sting c Tentacles have sticky surface to trap prey d Better digestive system e Better control of movement Acoelomates a Phylum Platyhelminthes platy flat helminthes worm like i Have a branched GV cavity ii Intracellular and extracellular digestion 1 Will begin to digest themselves if there is not enough food iii No circulatory or respiratory system iv v vi vii V 1 Explains why they are flat and not very broad need to use diffusion and diffusion is ineffective across long distances 3 germ layers Excretion via flame cells in protonephridia Only one opening for food and waste Have nerve cords and ganglia 1 Ganglia do not serve as a brain but more like a processing unit that is able to sense light with eyespots 2 Use ganglia to facilitate communication between sides of body Bright colors serve as warning signs for other animals Bilateral symmetry viii ix b Classes i Class Turbellaria Ex Planaria 1 Most are marine some are freshwater few are terrestrial 2 Predators and scavengers 3 Body surface is ciliated 4 Eyespots ii Class Trematoda commonly called flukes 1 Parasites have varieties of hosts that are usually vertebrates iii Class Cestoda commonly called tapeworms 1 Head region scolex a Contains hooks and sucker 2 Has packets of reproductive proglottids a Packets contain thousands of eggs b Packet will break off in hopes of getting elsewhere 3 Reproduce asexually through proglottids Pseudocoelomates a Phylum Rotifera commonly called rotifers i Cell constant animals meaning that it is exactly the same size ii Once a cell is lost it is not replaced by mitosis because these creatures cannot do mitosis after embryonic development iii Has a grinding organ called a mastax or trophi iv Can have parthenogenesis where the eggs develop without being fertilized by sperm v Bilateral symmetry vi Sexual reproduction only happens during hard times b Phylum Nematoda commonly called round worms hookworms and filaria worms i Longitudinal muscles only so there is not a whole lot of controlled movement ii Some are parasitic and some are free living iii Hydrostatic skeleton iv Bilateral symmetry VI Coelomates a Phylum Nemertea commonly called proboscis ribbon worms i coelomate classification is just up for question ii differs from flatworms in 2 major ways 1 one way digestive system 2 simple circulatory system