Animals General Characteristics of Animals Chapters 29 to 34Here is how you will set up your foldable. Invertebrates Vertebrates Early Humans Fishes Amphibians Reptiles Birds Sponges Mollusks Annelids Arthropods Echinoderms
General Characteristics of Animals • Over 1 million species identified • They are classified by SIZE, SHAPE, BEHAVIOR. • Animals have the following in common: -heterotrophs – get food from somewhere else -mobility – can move -multicellular – made of more than one cell -diploid (one gene from mom and one from dad) -sexual reproduction -cell organization into tissue -no cell wall on their cells • Evolutionary relationships determined by FOSSIL RECORDS. • Direct evidence of relationships by DNA.
Body Symmetry Body Plan– describes the animal’s shape, symmetry and internal organization. The organism can be divided equally around a central point. The organism can be divided equally in half. The right and the left sides are exact the same. HUMANS
Let’s Practice SymmetryGrab a colored pencil asymmetrical radial bilateral
Invertebrates • Are organisms that do not have back bones.
Porifora – “Sponges” • Lack symmetry • They are a mass of specialized cells embedded in a gel-like substance. • Sponges have three parts: -ostia – tiny opening or pores where water enters. -oscula – where water exits. -sessile – where the sponge attaches to the bottom of the water. • They get their food by filtering organisms out of the water. Let’s see a sponge feeding!
Cnidarian – Stinging Cells There are two shapes that cnidarians come in: medusa and polyp – radial symmetry Attached to rocks or other objects Free floating Anthozoans Hydrozoans Scyphozoans Coral and sea anemone jellyfish hydra
Platyhelminthes – Parasitic Worms Flatworms • Found mostly in marine water. • We usually study the planarian because it can live in captivity.
Nematodes– Parasitic Worms Roundworms -mostly found as a parasite in dogs (canines) -They have long, cylinder-like bodies with a one way digestive system. -There are 50 species of roundworms that can do damage to animals, people or plants.
Annelids • Segmented worms (earthworms) – date back 530 millions years ago. • They believe that they originally lived in the sea and 2/3 still do. • They have very basic brains and a nerve chord under the body. • They have 4 major parts: -digestive system -excretory system (poop) -circulatory system -locomotion – move with parapodia (bristle like structures) • They are good on land because their waste contains nutrients for soil and they aerate the soil.
Mollusks • Examples: snails, slugs, oysters, clams, scallops, octopuses and squid. THEY ALL HAVE: • A body cavity called a COELOM. All organs are in the cavity, suspended in fluid and attached to the body wall. • Bilateral symmetry. • They all have body systems • Most have one or two shells (not all) • Most have a radula for eating: used to scrape particles of food
Mollusks The mollusks without shells via water jet propulsion - SQUID. The mollusks with shells: A. Have three body parts (especially the ones with shells): -mass – central section that contains organs. -mantle – heavy fold of tissue that makes up the outer body. -foot – muscular region that is used for locomotion. B. Many have shells that serve as PROTECTION and a place for MUSCLES TO ATTACH.
Arthropods • Major Evolutionary Advancement is appendages – structures that extend from the body and have joints. • They have a coelom and segmented bodies. • 2 groups– ones with jaws and ones with fangs/pincers. • Exoskeleton made of chitin, that is hard and surrounds the body. • To grow larger, they shed their exoskeleton and grow a larger one. • Examples – centipedes, millipedes (eat decaying plants), ticks(carry Lymes Disease), spiders, lady bugs, shrimp, scorpions, horseshoe crabs, grasshoppers, butterflies, crayfish.
Butterflies go through a complete metamorphosis. In a chrysalis
Echinoderm • They are spiny invertebrates that live on the ocean bottom. • Examples: sea stars, sea lillies, brittle stars, sea urchins, sea cucumbers. • They are all very different but have 4 things in common. -endoskeleton - skeleton made of calcium inside the body. -5 part radial symmetry. -Water vascular system – filter water for food and oxygen. -Coelomic and respiration – to get rid of waste and breath through gills.
More Echinoderms • The other group of echinoderms are called invertebratechordates. They have an endoskeleton that includes a notochord – a stiff rode that runs down the back. They can move their bodies side-to-side. Lancelet – resembles a fish. Cannot be found in shallow ocean water. Filters protists from the water. Tunicates – Filter feeding marine animals
Vertebrates Chordates with a backbone that provides support, protects the dorsal chord and provides a place for muscle attachment .
Vertebrates • The backbone allows the organism to grow larger than an invertebrate. Got it’s name from the segmentated backbone. • Bony skull to enclose brain that is higher functioning and can sense. • Bilateral symmetry. • 2 pairs of jointed appendages (limbs or fins). • First vertebrates were fish. • First land vertebrates were amphibians. ECTOTHERMIC Metabolism too slow to maintain body heat so the organism has to absorb heat from the environment. ENDOTHERMIC Can maintain constant temperature by producing it internally.
Review of the Evolution of Humans Homo habilus Handy Man Tools Homo erectus Upright Man Fire Homo sapien Wise Man Abstract Thinking
Fish – First Vertebrates Not all fish look “fishy”. There are three groups MAJOR CHARACTERISTICS IN COMMON. -Gills – they obtain oxygen (gas dissolved in the water) from the water. -Swim Bladder – allows fish to go up and down in the water (bouyant) -Single-loop blood circulation– blood pumps from the heart, to the gills, gills to the rest of the body and back to the heart. -Vertebral column– have an internal skeleton made of cartilage or bone.
Three Types of Fish • Jawless – scaleless, eel-like fish with multiple gills and unpaired fins. Examples: lampreys and hagfish. • Cartilaginous – Their bodies are all cartilage and strengthened by calcium carbonate. Examples: sharks, skates and rays. • Bony Fish – Most and diverse group of fish. Strong internal skeleton made of bone. They have a swim bladder which regulates buoyancy.
What adaptations were necessary for animals to live on land? Legs Lungs Complex Heart Structure
Amphibians – First vertebrates on land • Examples: frogs, toads, salamanders and newts. • They all have four legs. • Partially divided heart – it has a right and left side. • They have lungs but they must live near water to stay moist and breath. • Cutaneous respiration – they supplement breathing by respiring through the skin.
Reptiles • Strong body skeleton with toes and claws. • Ectothermic and breath through lungs. • Dry, scaly, almost water tight skin. • Lay eggs to reproduce (internal reproduction like birds). • Ventricle heart divided by septum. Many people tend to be afraid of these organisms. Crocodiles, alligators, lizards, turtles and snakes SNAKES - different features; flexible body, swallow prey whole, lack moveable eyelids and external ears).
Birds • They retain many characteristics of reptiles but have the ability to fly. • Lack teeth. • Reduced tail length. • Front limbs are wings not legs. • Bodies covered in feathers which are MODIFIED SCALES – the body secretes oil from the PREEN GLAND to waterproof the feathers. • Light and hallow bones. • Endothermic metabolism. • Great respiratory system for flying long distances. • Heart divided into 4 chambers, divided by a septum, like mammals.