Final Exam - Invertebrates PDF

👾 Final Exam Invertebrates animals without backbones very diverse: more than 90% of known animal species. octopus, starfish, jellyfish, crab, squid sea urchin, nautilus, lobster, clam, shrimp, barna...

👾 Final Exam Invertebrates animals without backbones very diverse: more than 90% of known animal species. octopus, starfish, jellyfish, crab, squid sea urchin, nautilus, lobster, clam, shrimp, barnacle, coral Major groups include porifers (sponges), cnidaria (jellyfish), Mollusca (snails, clams, octopuses), arthropods (crabs, shrimp, lobsters), Annelida (marine worms) Porifera known as sponges, live in marine/freshwater environments approx 5500 species lacks tissue and organs. They range in size from a few millimeters to two meters brightly colored (red, orange, yellow purple) do not have a nervous system Cnidarian Most cnidarians, aside from corals, have soft bodies over 10,000 species including jellyfish, sea anemones, hydra, corals cnidocytes present typically stinging organelles called nematocysts they have no true organs or organ systems they are widespread in marine habitats or freshwater. there are two variations in the body plan: the sessile polyp and motile medusa Final Exam 1  polyp adheres to the substrate by the aboral end of its body medusa has a bell-shaped body with the mouth on the underside. It is free moving. Classes: Anthroza - corals and sea anemones, scyphozoan- swimming jellyfish, stauroza- stalked jellyfish, cubozoa- box jellyfish, hydrozoa- hydroids and siphonophores Mollusca Mollusca are a very diverse group of organisms which includes slugs, oysters, clams, octopuses, squids, bivalves, snails humans have exploited these animals the majority are marine but also live in freshwater and some slugs are terrestrial they occupy habitats that are free-living or parasitic. classes: Polyplacophora- chiton, Gastropoda-(abalone, snails, snugs). Bivalvia- (clams, scallops, mussels, ) , cephalopods- (squid, octopus) Arthropoda have an exoskeleton, segmented bodies, and jointed appendages they have well-developed organ systems they fund in nearly all habitats of the biosphere the most diverse group in the sea crustaceans (shrimp, lobster, crabs, barnacles, etc) landforms - insects, spiders, scorpions, mites marine forms - horseshoe crabs, sea spiders, crustaceans (barnacle, shrimp, lobster) Echinodermata have two surfaces: oral (mouth and tube feet project are found here and aboral (contains the anal opening of the digestive system) starfish Final Exam 2  Annelida (Marine worms) segmented worms polychaetes (bristle worms are the most diverse) bamboo worms, fire worms, Christmas tree worms Vertebrates animals with backbone fish, reptiles (eg: sea turtles), birds (eg: seagulls), mammals (eg: dolphins) Chordata (deurterostomes) notochord- replaced by the vertebral column during development nerve cord- develops into the brain and spinal cord pharyngeal gill slits- gills in fishes post-anal tail - aids in locomotion endostyle- evolves into the thyroid gland Urochordata (tail-chordates)- sea sqaure the urochordate are commonly called tunicates and include 3000 species Final Exam 3  they live in the sea and are mostly sessile (nonmoving) as adults they have tough, nonliving tunic, that surrounds the animal and contains cellulose in some groups, only the larval form has all the characteristics of chordates Cephalochordata they are lancets: slender compressed, translucent animals, about 3-7 cm in length that inhabit sandy sediments and coastal waters they have a bladelike shape they have a slightly swollen tip on the anterior end of their dorsal nerve cord but no true brain they have colorless blood that moves through a ventral vessel they feed on plankton as larvae and as adults, they bury their bodies in the sand and filter for food Fishes larges and most diverse of marine vertebrates three main groups: jawless fishes (agnatha): hagfish and lampreys cartilaginous fish (chrondrichythes ): sharks and rays bony fish (osteocytes): tuna and clown fish Agnatha (Jawless fish) they have pore-like gill openings and eel-like body form they lack jaws, internal ossification, scales, and paired fins. they have pore-like gill openings and eel-like body form skeletons consist of cartilage predation is common among this group. hagfishes: myxini have no vertebrate Final Exam 4  soft skinned and scales eyes are covered with skin they are blind usually found in cold, marine bottom waters lampreys: petromyzontida parasitic with moderately developed eyes and makes skin they are commonly found in marine environments as adults but found in freshwater move/swim by undulations of the body well known for attacking salmonid fishes. It staches to prey using the suctorial mouth Chrondrichythes (eg: shark) distinct feature is cartilaginous skeletons The skeletons are extensively calcified and the bones are absent they have well-developed brains, senses of smell, vibration (lateral line), electroreception, and vision sexes are separate: internal fertilization with claspers they are divided into two classes. Elasmobranchii (shark, rays, and skates) and Holocephali (chimaeras) Osteichythes also called bony fish - internal skeleton is completely made of bones this is the most species-rich group of vertebrates (more than 30k species) teo major sub-classes Actinopterygii (ray-finned fishes) sarcopterygii (lobe-finned fish) Ecology- refers to an organism and its environment coined by German zoologist Ernst Haeckel in 1866 Final Exam 5  Eco comes from the Greek “oikos” meaning household, home, or place to live Ology- study of Ecology the scientific study of the distribution, abundance, and dynamics of organisms, their interaction with other organisms, and their physical environment. organism or individual→ population→ community→ecosystem→ biomes→ biosphere Species or Orgnaims a group of organisms with shared genes, capable of sexual reproduction to produce fertile offspring. native species- native to the environment alien species- not from there, but introduced into the environment, however they are not harming invasive- species introduced but causing harm to the environment Population a group of individuals of a given species that live in a specific geographic area Community population of species living in a defined area (habitat or ecosystem) and interacting in various ways it can be defined based on taxon(birds), habitat, or ecosystem (marine ecosystem) Ecosystem coined by AG Tansley a biological community interacting with abiotic components of its habitat Note: habitat sets the physical parameters of the system Habitat Final Exam 6  the area in the ecosystem is defined by physical and chemical characteristics suitable for supporting the life of a species microhabitats are small areas within the habitat Life in Marine ecosystems can be divided by depth (vertically) or distance from land (horizontally) different zones of the ocean have conditions that support different organisms Ecological Interactions the range of ways in which individuals (same and different) species, colonies, and populations interact with each other Mutualism both organisms benefit (eg: clownfish and sea anemones) Commensalism one benefits but another is not disturbed (eg: remora fish and sharks) Parasitism one organism benefits but another one is harmed. (eg: copepod parasites and fish) it can live within or on the host. Predation one organism kills another Competition two or more organisms accessing similar resources that are limited intraspecific competition- competition among the same species interspecific competition - competition among different species Feeding Ecology Food web Food chain Final Exam 7  producer→ primary consumer→secondary consumer→tertiary consumer→quatermary consumer Final Exam 8