380 likes | 622 Views
Animals. What does it mean to be an animal?. Multicellular Eukaryotic Ingestive Heterotrophs Lacking cell walls Have a mobile stage in their life cycle. Divisions. Vertebrates – with backbone protecting nerve cord Invertebrates (lacking backbones) make up 95% of all animals. Porifera.
E N D
What does it mean to be an animal? • Multicellular • Eukaryotic • Ingestive Heterotrophs • Lacking cell walls • Have a mobile stage in their life cycle
Divisions • Vertebrates– with backbone protecting nerve cord • Invertebrates (lacking backbones) make up 95% of all animals Porifera
Essential functions • Feeding - all are ingestive heterotrophs • Respiration – obtaining oxygen • Circulation – movement of materials into and around organisms. • Excretion – Getting rid of wastes produced by the organism’s metabolism • Response – Responding to events in environment • Movement – Sessile (immobile) or mobile Some have muscles for movement • Reproduction – Most by sexual reproduction. As you go up the evolutionary tree, we see a trend from asexual reproduction to sexual reproduction
Trends in Animal Evolution • Cell specialization and levels of organization • Cells differentiated to serve a particular function • Unicellular organisms do not have specialization beyond organelles. • Multicellular organisms have structures to serve a particular function • Nerve cells, blood cells, epidermal cells • Cells, tissues, organs then organ systems
Body Symmetry How the body can be divided to get two equal parts • Not found in Porifera (Asymmetric) • Radial symmetry can be cut in any plane from top to bottom to get two equal parts – Cnidarians • Bilateral symmetry – can only be cut in one plane – everything besides Porifera and Cnidarians
3. Cephalization Concentration of sensory structures (nerves) towards to anterior (front) region of the animal) 4. Central Nervous System – brain and spinal cord
Body views • Anterior – front of animal closest to head • Posterior – hind end of animal, what comes last • Dorsal – back end or end that faces up • Ventral – bottom end or end that is against the ground
Porifera Porifera means “pore-bearer”
Sea sponges Porifera “Pore bearing”
Interaction with humans • Extract used to stunt the growth of cancerous tumors • Indicators of marine environmental health • Original bath sponge came from sea sponges Stagehorn sponge
Cnidaria CnidariaStinging celled animals • Phylum- Cnidaria • Meaning-stinging needle Jellyfish Stinging Hydroid Sea Pen Fire Coral Sea Anemones
Cnidarians all have radial symmetry Coral Sea anemones Hydra Jellies Mushroom Coral Box Jellies Pink-Tipped Surf Anemone Siphonophores Hydroids Fire Coral Sea Pen Jellyfish
2 basic forms • Tentacles Down = Medusa • Tentacles Up = Polyp • Reproduce asexually by budding Relation to Humans • Coral – jewelry • Global warming/pollution bleaching out coral beds • Have biomedical compounds -anti cancer properties • Habitats for fish/ snorkeling
Nematoda“thread”Round worms Threadworm Roundworms Soybean cyst nematode Porkworm
External and Internal Structures of Nematoda • Unsegmented worms • Some are parasitic • Found in soil & water • Have a digestive tract with mouth and anus • Obtain oxygen through body wall & diffuse out wastes • Simple nervous system w/ ganglia in head running down the length of the body • Sexual reproduction but separate sexes. • Internal fertilization
Parasitic nematodes infect humans • Pinworm • Hookworm • Filarial worm • Beneficial nematodes help soil
Platyhelminthes Platyflat Helminthesworms. Therefore: Flatworms Tapeworm Planaria Turbellaria
Characteristics • Soft, flattened bodies • Oxygen & wastes diffuse through skin • Mouth with tube-like pharynx for food getting • Have a gastrovascular cavity for digestion & absportion • Flame cells to filter, remove excess water & metabolic wastes • Gangliaanteriorly with twoocelli(eyespots) to detect light. • Nerves run down sides
Mostly sexual as hermaphrodites Capable of regeneration
Tapeworm • Live in intestines of vertebrates • Enter host through undercooked or raw meat containing eggs
Phylum- Annelida • Latin root Annellus • Meaning little ring • Segmented worms: • Earthworms • Sandworms • Leeches
Internal and External Structures • Body divided into segments – separated by septa (walls) • Complete digestive tract • Mouth, pharynx, esophagus, crop, gizzard, intestines, anus • Body wall (epidermis) is thin to allow for gas exchange • Kept moist with mucous • Closed circulatory system consisting of five aortic arches (hearts) with a dorsal and ventral blood vessel • Simple anterior brain & ventral nerve cords clittelum
Feeding- pharynx or filter feeding -soil -decaying vegetation • Reproduction- • - Sexually – cross fertilize • - Hermaphroditic • - Clittelum – thick band that produces mucous ring for eggs • Movement- • - Setae - paired bristles • - Muscles – longitudinal & circular
Human Interactions • Keep soil aerated • Leeches- prevent blood clots • Leeches are parasites
Soft bodied animals Mollusca Gastropods Bivalves Cephalopods
Have internal (squid) or external shell Snails, slugs, clams, squid & octopi Use foot to attach and mucus to slide for movement In snails and slugs - Radularasping device to abrade the food Bivalves use a siphon to pull in food with water Radula
Some hermaphodites • Cephalopods have a jet propulsion system & haveink sacs/glands Bivalves are filter feeders & clean up water of algae Use bivalves to monitor water conditions since they filter toxins & pollutants Jewelry and currency Excellent food!
ArthropodsJointed Legged animals • Jointed appendages • Exoskeletons of chitin • Segmented bodies (head, thorax, abdomen) • Open circulatory systems • Insects, spiders, crustaceans, millipeds, centipeds, trilobites
Butterflies, flies, moths, bees, ants, beetles, grasshoppers, dragon flies, … Body in three parts: Head, Thorax and Abdomen 6 jointed legs 2 pairs of wings Compound eye 2 antenna Insects
Reproduction, Respiration & Feeding Reproduction - Sexual – separate sexes - Metamorphosis – complete & incomplete Incomplete metamorphosis
How insects move and interact with humans • Pollinate plants • Bite or sting humans • Spreads diseases • Cause major plant damage • Honey
EchinodermataSpiny skinned animals Sea Star Sea cucumber Sand dollar Urchin Sea star eating a clam
Tube feetunder rays • Small hollow tubes • Create suction on the end • Used for food getting, respiration & movement • Connect to Water Vascular System -
Interaction with humans • Used for food (sea cucumber or urchin soup) • Used in embryological studies since their embryologic development is like that found in vertebrates. Similar gastrulation • Jewelry • Wipe out clam beads • Major threat to coral reefs – Crown of Thorns sea star Sea cucumber