Anthropod
Arthropods (joint foot)
Form and Function: EXOSKELETON- insects: flexible ticks & lobsters: hard
Many terrestrial have H2o proof exoskeleton, making it possible to live in extremely dry places.
Jointed Appendages; enable movement. Examples: claws, antennae, legs, wings, flippers, etc.
Segmented bodies: Most have 3 segments. Centipede and millipede have more. Some have 2, because head and thorax= cephalothorax.
Respiration: crustaceans: gills, chelicerates: book gills and book lungs, insects: tracheal tubes
Internal transport: well developed heart pump blood into open circulatory system
Excretion: solid waste -anus Nitrogen wastes – Most terrestrial: malpighian tubules remove waste from blood, concentrate it, and mix with undigested food before leaving through anus. some terrestrial: excretory glands at the base of legs. Aquatic: heads(green gland)
Response: brain have a pair of ganglia in head. recive information and send instructions to muscles. Ventral nerve cord connects brain with body and other gaglia that control legs and wings. Crustaceans and insects have good taste and smell.
Movement: muscles pull exoskeleton to move
Reproduction: separate sexes. dioecious: internal fertilization.
spiders and someCrustaceans: male deposits packet of sperm for female to pick up.
Most crustaceans and insects: male use reproductive organ to deposit the sperm inside female.
Crustaceans: crabs, shrimps, lobsters, crayfishes and barnacles.
Arachnids: spiders, mites, ticks, and scorpions. Spiders spin web by forcing liquid sild through spinnerets, organs that contain silk glands.
Insects: have jaws, one pair of antennae, and unbranched appendages.
Uniramianss-insects
Chelicerates-horseshoe crabs, spiders, ticks, and scorpions.
Incomplete metamorphosis: insects molt several times. larva that looks like adult, but lack sex organs and wings. As they grow they will gradually acquire adult characteristics.
Complete metamorphosis: 4 stages: larva looks nothing like adult-molts and grows-pupa, during which body is rearranged-Adult structures grow fom tiny buds and use the lava structures as raw materials.
crayfish: have cephalothorax, which is covered by carapce that covers the gills
Grasshoppers: leathery front wings, thrid pair of legs is suited to jumping, trypanum on sid of first abdominal segment. Food enters through chewing mouth segments-stored in crop, gastric mill grinds food before stomach digests it. Malpighian tubules extend into coelom. Spiracles lead to trachae that diffuse gases for respiration. Tubular heart pumps hemolymph through open coelom. Reproduce by copulation. Female stores sperm in sminal receptacle, then deposits eggs in ground by ovipositor to overwinter.
Insects use sound, chemical receptors, and other types of signals to communicate. Pheromones are specific chemical messsengers that affect behavior or development in other individuals of the same species.
a society is a group of animals of the same species that work together for the benefit of the whole group.
Echinoderms(spiny skin): characteristics: spiny skin, 5 part radial symmetry, internal skeleton, water vascular system, tube feet, diverse phylum.
Similarities to verteberates: similar larvaa to development to chordates. Internal skeleton.
Mouth is on oral surface, opposite is aboral surface. WVS is similar to hydrolic pumps.
Feeding: carnivores(starfish): pry open shells of bivalves with tube feet. Flip stomach to digest food in the prey’s shell. Herbivores(Seaurchins): scrape algae using 5 part jaw. Filter feeders(brittle stars): use tube feet to catch food floating by. Detritus feeders(sea cucumbers): move like bull dozer across the ocean, eating everything.
Respiration: Most use tissue of tube feet. Some(stafish) use sking gill
IT: water vascular system replaces system for gas exchange. Nutrient distribution done by digestive glands and fuid in body cavity.
Excretion: sloid wastes through anus, ammonia excreted by tube feet and sking gill
Response: most have nerve ring around mouth and radial nerves that connect the ring with the body sections. Scattered sensory cells detect food chemicals. Starfish have clusters of up to 200 sensitive cells called eye spots. Statocysts tell if organism is rigtht side up
Reproduction: Most echinoderms have separate sex. egg and sperm are releasesed in the water, so fertilization occurs in open water. Larvae swims in the plankton community until they mature and metamorphosis into adults.
Classes: starfish-radial symmetry(5-16). Sea Urchins and sand dollars: sand dollars are disc shaped, sea urchins are oval shaped. Sea cucumbers: oval, round.
Water vascular system: used for feeding, repiration, internal transport, elimination of waste, and movement.