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How Animals Function

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How Animals Function Phylum Arthropoda: jointed appendages Abundance: There are about a billion billion arthropods Diversity: 2/3 species is an arthropod Ecdyzoa group: Nematoda and Arthropoda They have a cuticle that must be molted via ecdysis Nematods are pseudocoelomates and have no segmentation Arthropods are coelomates and have segmented bodies 1 Arthropods secrete to success Segmented body with appendages Arthropods secrete to success Segments fused and Exoskeleton (cuticle with chitin and hardened by protein matrix) Appendages became specialized (division of labor) structural support, protection, prevention from water loss levers for muscle attachment and movement joints (areas where cuticle is thin) provide flexibility Need to molt allowed for: Metamorphosis radical change in form between larva and adult 2 Limitations of being an arthropod Phylum Onychophora: Velvet worms Phylum Tardigrada: Water bears 3 Phylum Arthropoda: arthropods Subphylum Myriapoda: millipedes and centipedes Subphylum Myriapoda: Subphylum Chelicerata: spiders, scorpions, ticks, mites Subphylum Crustacea: Crayfish, crabs, shrimps, barnacle, roly-poly Body divided in 2 regions: Subphylum Hexapoda: insects and relatives Head and trunk Young resemble adults No metamorphosis 4 Subphylum Myriapoda: Subphylum Myriapoda: Class Chilopoda: centipedes Class Diplopoda: millipedes Have flattened bodies with up to 177 segments - Less active than centipedes Each segment bears ONE PAIR of jointed legs Walk with graceful rather than wriggling motion appendages of first body segment form poison claws - Scavengers: most eat decayed plants but a few eat living plant tissue Head has one pair of antennae, a pair of mandibles, and one or two pairs of - Most are slow moving and roll into a coil for defense maxillae - Some secrete toxic or repellant fluids - Cylindrical bodies with 25 to more than 100 segments Predators, most harmless to humans Most segments have two pairs of legs Young resemble adults and do not undergo metamorphosis 5 Subphylum Chelicerata: arthropods with claws Body divided in 2 regions: Cephalothorax (sensory, feeding, locomotor) abdomen (visceral functions) 1stpair of appendages are chelicerae (feed/defense) 2ndpair are pedipalps(sensory) Kingdom Animalia: Phylum Arthropoda Lack mandibles and antennae (Subphyllum Chelicerata) Most suck liquid food from prey 6 Class Merostomata: Horseshoe crabs Why this crab's blood could save your life - Marine in shallow waters, come to shore to mate - Feed on worms and mollusks http://www.cnn.com/2014/09/04/health/this -crabs-blood-could-save-your-life/ - Unchanged for 250 million years - Unsegmented carapace covers body Horseshoe crab blood can detect and trap bacterial toxins - Cephalothorax: 5 pairs of walking legs and 1 pair of chelicerae Its blood is harvested for a test to ensure medical products are not contaminated. - Abdomen bears six pairs of thin appendages 45 minutes of exposure to the crab's blood is enough to reveal bacteria - Carapace has 2 compound and 2 simple eyes contamination which otherwise avoid detection It is sensitive enough to isolate a threat the equivalent size of a grain of sand in a swimming pool. The U.S. Food and Drug Administration (FDA) requires that intravenous drugs and any medical equipment coming in contact with the body must first pass through the crab's blood, from needles to surgical implants including pacemakers. As a result, thousands more of us survive such procedures. Up to 600,000 crabs are captured each year for their blood Between 10-30% of donor crabs die in the process 7 Class Arachnida: Spiders, scorpions, ticks and others • Cephalothorax: a pair of chelicerae, a pair of pedipalps, and 4 pairs of walking legs • In spiders abdomen spinning glands • Most are predators and have claws, fangs, poison glands, or stingers • Pedipalps of males are modified for sperm transfer • Most harmless to humans and provide essential control of injurious insects • Ticks may carry human diseases (Lyme disease) 8 Subphylum Crustacea: crustaceans Kingdom Animalia: Body divided in 2 regions: Phylum Arthropoda Cephalothorax (sensory, feeding, locomotion) may be covered by ________, has 2 pairs of antennae (Subphylum Crustacea) Abdomen with swimmerets and uropod (swimming, reproduction and breathing) Biramous appendages (branched) 9 Crayfish dissection: External anatomy Crayfish dissection: Internal anatomy Labeled structures include one of the two green glands (1) that function in osmoregulation and excretion, one of the compound eyes (2), the digestive gland (3), one of the two sets of mandibular muscles (4) that control the mandibles, the gills (5), a portion of the abdominal extensor muscle (6), a portion of the fifth walking leg (7) and one of the third maxillipeds (8). 10 Class Maxillopoda: barnacles and copepods Crayfish dissection: Internal anatomy • Copepods are small in size and lack abdominal appendages • Main component of zooplankton • ½ species are parasites of other marine animals • Most feed with their maxillae but barnacles use their legs for filter feeding, . 11 Class Malacostraca: Crayfish, lobsters, crabs , shrimp , krill and pill bugs Marine, freshwater and land Most species are scavengers, although some, are filter feeders (porcelain crab) are carnivores (mantis shrimp) are parasites (isopods) Note that in crabs the abdomen is folded under cephalothorax 12 Phylum Arthropoda: arthropods Subphylum Myriapoda: millipedes and centipedes Subphylum Hexapoda: Subphylum Chelicerata: spiders, scorpions, ticks, mites Body divided in 3 regions: Subphylum Crustacea: Crayfish, crabs, shrimps, barnacle, roly-poly Head, thorax and abdomen Subphylum Hexapoda: insects and relatives 3 pairs of legs Class Insecta: Mouth appendages exposed 13 No metamorphosis Incomplete metamorphosis with chewing mouthparts Order Orthoptera Order Thysanura Grasshoppers , crickets, roaches SILVERFISH 2 pairs of wings (forewings are leathery) Wingless, walking legs jumping hind legs Caudal filaments Chewing mouthparts Order Isoptera Termites 2 pairs of wings that are the same Order Odonata Dragonflies and damselfies 2 pairs of wings with primitive venation 14 INCOMPLETE METAMORPHOSIS with sucking mouthparts Grasshopper: external anatomy Order Hemiptera True bugs 2 pairs of wings (forewings are half hard) 15 COMPLETE METAMORPHOSIS WITH SIPHONING MOUTHPARTS Order Lepidoptera Grasshopper: internal anatomy Butterflies and moths Wings with scales walking legs 16 COMPLETE METAMORPHOSIS WITH REDUCED HIND WINGS (HALTERES) COMPLETE METAMORPHOSIS WITH CHEWING MOUTHPARTS Order Diptera Order Coleoptera Flies BEETLES Sponging mouthparts Forewings hardened (elytra), 2nd pair of wings walking legs Maggot therapy Order Hymenoptera ANTS, BEES, WASPS Mosquitoes 2nd pair of wings Piercing sucking mouthparts Abdomen with a waist, wings membranous, lapping-chewing mouthparts 17 Insects for food and as food 18 .
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