Review: Vertebrates and Invertebrates

15 Pages
Unlock Document

Northeastern University
BIOL 1115
Melissa Mc Elligott

Henry Hsu TEST #4/FINAL PHYLUMANNELIDA (protostome- first opening is the mouth) (eucoelomate - a “true” coelomate) ● metamerism - segmentation ○ Septa - segmented partitions that divide the internal, fluid filled coelom (Hydrostatic Skeleton) ○ Annuli ○ nephridia in most segments - excretion ○ setae on most segments ○ branched blood vessels in each segment ○ ADVANTAGES ■ lost body segment => other segments can take over functions ■ flexibility and locomotion (peristalsis -> wavelike movements) ● specialized digestive tract ● Closed circulatory system ● ventral solid nerve cord ● most are marine ● Setae/Chetae(chitin)- bristles that help the organism move 1. POLYCHAETES ● Sedentary (confined within burrows) and errant polychaetes (actively mobile) ● have prostomium, peristomium, parapodia, and many setae ○ Parapodia - paired fleshy appendages (for locomotion and respiration) Jaw Parts ○ Prostomium - region above the mouth [ex.)eyes] ○ Peristomium - region around the mouth (contains mouth) ● trochophore larva ● Atoke - the anterior sexless part of certain polychaete worms ● Epitoke: modified reproductive segment of worm (posterior), “swarming” is simultaneous release of all eggs and sperm ● Pogonophora (Siboglinids) ○ habitat: near hydrothermal vents ○ SYMBIOTIC relationship with chemosynthetic bacteria - uses organism waste to produce organic material (food) ■ Trophosome: organ filled with chemosynthetic bacteria, feeds worms -> worms dependent upon bacteria for food ● Oligochaetes ○ no well-developed head or parapodia ○ Has dorsal blood vessel ○ setae protrude in pairs from surface of body ○ food drawn into mouth by muscular pharynx ○ Clittellum - secretes mucus to protect sperm from dessication (cocoon) ■ cross fertilization (hermaphroditic) ○ Typhlosole - absorption in digestion ○ Crop: expanded region for storage ○ Gizzard: area for grinding, stones of calcium carbonate ● Hirudinea - Leeches ○ No setae, no head ○ 2 suckers for attachment (anterior and posterior) ■ “temporary parasites” – don’t maintain consistent relationship with body of host ■ not all feed on blood ○ Have a three-plated bite (triradiate pharynx) ■ Jaws built out of series of chitinous plates ○ Hirudin: powerful anticoagulant, prevents the blood from clotting (keeps blood flowing from body of prey into leech) ○ Digestion incredibly slow -> GI tract does not produce any enzymes, symbiotic bacteria responsible for digestion ○ Medical uses: surgery, remove clotted blood Phylum Arthropoda GENERAL CHARACTERISTICS: (protostome development- first opening is the mouth) (Eucoelomate- true body cavity, triploblastic (3 germ layers)) (metamerism- segmented body of repeating units) (tagmata- grouping of specialized segments) -Ex: head/cephalothorax,thorax, abdomen (exoskeleton made of chitin- varying thickness between classes) (have jointed appendages) (hemocoel- series of spaces between organs allowing blood circulation) -aka: open circulation (tracheae-land inhabitants only- diffusion of O2) (spiracles-surface openings on land organisms allowing gas exchange “through” exoskeleton) (digestion:) terrestrial: malpighian tubules marine/aquatic: green glands ● Head: feeding and sensory appendage ● Setae: sensory hairs, provide information about surrounding environment ● Thorax: designed for locomotion (i.e. jointed legs and wings) ● Abdomen: bulk of internal organs ● Ecdysis: molting, the periodic shedding of old cuticle and formation of new cuticle ○ Premolt Stage: animal breaks down old cuticle and at the same time epidermis is beginning to produce new cuticle, new cuticle is highly folded (two cuticles at the same time) -> old cuticle gets thinner, new one is being produced ○ Molting: old cuticle ruptures and animal moves out of old cuticle and is now covered by new, softer cuticle (new cuticle stretches out) ○ Post Molt: cuticle solidifies (strengthens) and exhibits normal characteristics ■ Tanning – proteins cross-linked together (skeleton hardens) ○ Controlled by hormones: ■ Y-organ – produces ecdysone (molting hormone) which triggers events of molting ■ X-Organ – produces molt inhibiting hormone (MIH) which shuts off events of molting ● Gastric Mill: grinding set of plates ● Metamorphosis - variety of stages in life history SUBPHYLUM CHELICERATA ● ex: spiders, scorpions, ticks, mites, HORSESHOE CRAB ● HS Crab: telson only line of defense, blood clots in presence of bacterial endotoxins ○ LAL(Limulus Amoebocyte Lysate): horseshoe crab blood clots in presence of bacterial endotoxins -> blood cells taken from blood and frozen (called LAL) and then used in tests to ensure medical equipment is sterile and clean ● chelicera - pincer-like feeding appendages, modified into venom-producing structures in spiders ● pedipalps - anterior shortened pair of appendages- “feelers” ● walking legs - periopods, attached to thorax ● carapace - section of exoskeleton covering ventral portion of cephalothorax ○ crustaceans+arachnids ● telson - rearmost “segment” of body ○ ex: middle lobe of lobster tail, scorpion stinger ● book gills - aquatic respiration, look like pages of book ● hemocyanin - O2 transport proteins ○ invertebrate version of hemoglobin CLASSARACHNIDA -poison glands: -black widow- neurotoxin: paralyzes nervous system -brown recluse- hemorrhagic toxin: destroys capillaries+blood cell -fangs- attached to head, used for feeding/defense -> inject poison -silk glands- located posteriorly, produce web used for passive predation SUBPHYLUM CRUSTACEA ● Hard, calcified shell ○ ex: barnacles, water fleas, copepods, lobster, crab, crayfish ● Appendages are biramous (2-part, branched appendage attached to body surface) ● Sensory appendages: antennae and eyes ● Swimmerets: first pair modified for reproduction (claspers), help with tail flipping (animal will scoot in opposite direction of tail flip -> backwards) ● Neurogenic heart: beating of heart controlled by nervous system ○ Holes (ostia) in heart which allow fluid from open circulation to flow back into heart ● Copepods: food for other organism (enormous food source) ● Metamorphosis reduces competition (leads to juveniles and adults being successful due to different food sources) ● ecdysis - molting ● antennae- located anteriorly, used for sensing environment ● mandibles: mouthparts used for biting, cutting, holding food (attached exteriorly) ● maxillae- fusion of two plates forming upper jaw ● molting: see above SUBPHYLUM HEXAPODA CLASS INSECTA ■ 3 pairs of legs (6 total) ■ wings allow flight (1 or 2 pairs) ■ use tracheal system for respiration ■ undergo metamorphosis - dramatic change in body form ● egg -> larvae -> pupae -> adult ■ instar- successive stages between molts of increasing sexual maturity ■ holometabolous - complete metamorphosis, offspring do not compete with adults for resources ● Larval stage is worm-like, entirely terrestrial, herbivore ● Pupa stage is stage in which body encased by cocoon (pupa) ○ Extremely active stage of differentiation -> animal is experiencing a breakdown of larval structures and breakthrough of adult structures ○ Adult structures produced through imaginal discs ○ wings develop from internal structures (imaginal discs) ● Reproductively capable adult emerges from pupa stage ■ hemimetabolous - incomplete metamorphosis ● egg -> nymph (wingless version of adult) -> adult ■ ametabolous - no metamorphosis ● Insects change very little in body form as they develop -> just grow larger over time ● What hatches from egg are “mini” adults ***FROM HERE DOWN, ORGANISMS ARE DEUTEROSTOMES*** (mouth forms from second cavity) Phylum Echinodermata ● Deuterostomes - first opening is anus (instead of mouth) ● Radial, indeterminate cleavage (embryo can still develop if cell is taken out) ● radial symmetry ○ Pentamerous symmetry ○ trochophore larva - bilateral symmetry ■ undergo Metamorphosis - become pentamerous ● Endoskeleton (ossicles/spines - internal calcium rich plates) ○ Pedicellariae - Minute pincers (protect and clean animal[algae free]) ○ Dermal Branchiae - respiration ● exclusively marine ● no cephalization ● Extensive coelom (Water Vascular System) ● Madreporite: calcium-rich plate, entrance to water vascular system ● Water Vascular System 1. Madreporite - entrance 2. Stone Canal - pressure regulator 3. Ring Canal - runs around mouth a. Polian vesicles – regulate fluid within water vascular system (fluid storage) 4. Radial Canals (5) - deliver fluid into arms 5. Lateral Canals - have valves at ends that allow fluid to flow into ampullae 6. Ampullae 7. Tube Feet (Ambulacral Groove - houses tube feet) - external parts, allow for locomotion and help in feeding ● 2-part stomach: ○ Cardiac stomach: stomach that can be inverted out of mouth (comes out of mouth to grab food and then retracts into body) ○ Food moves from cardiac stomach into pyloric stomach, then into pyloric caeca (delivers nutrients to cells) ● Cardiac Stomach - attached to the mouth and comes out of the mouth to ditnutrients ● Pyloric (gastric) Caeca - digestive glands; deliver nutrients ● regeneration (Autonomy - can drop arms at will) ● Hemosystem: system present in echinoderms without known function, no direct connection to water vascular system ● Autonomy: ability to drop an arm at will (mutable connective tissue can change from being soft and pliable to hard in seconds as a means of protection) Phylum Chordata ● 4 Characteristics (occurs some point in all chordates) 1. Notochord - provides support & axis for muscles 2. Nerve Cord - dorsal, hollow; anterior end enlarges to form brain 3. Pharyngeal Pouches (Gill slits) 4. Post-anal Tail - evolved for water propulsion ● Other characteristics ● muscles ● ventral heart ● endoskeleton ● segmentation ● Tetrapods - 4 limbs, air less buoyant than land ● Cephalochordates [Lancelets (5-7 cm) - organism] ○ marine (fish-like chordates) ○ 4 chordate characteristics as Adults ● Urochordates [tunicates] ○ tunic for defense ○ sessile ○ filter feeder - siphons ○ Adult ■ pharyngeal gill slits ○ Tadpole Larvae ■ 4 chordate characteristics ○ VertebrateAncestor - explanation ■ Paedomorphosis - larvae characteristics get retained in adult form (evolution) ● precocious puberty ● slow body growth, but normal reproductive growth ○ Endostyle - responsible for control of metabolism ● Craniates ○ 2 defining characteristics 1. Cranium - nerve cord forms brain (bony/cartilaginous housing) 2. Neural Crest - group of embryonic cells on each side of neural tubes; contributes to skeletal development, nerves, jaws and teeth ○ 2 clusters of Hox genes ■ gene duplication (body part formation) ■ body pattern and development ■ vertebrates have 4 clusters ○ Not all craniates are vertebrates, but all vertebrates are craniates ■ b/c craniates lack a vertebral column ○ Hagfishes “slime eels” ■ marine, jawless, finless ■ lack vertebrae ■ have skull and cartilage notochord ■ scavengers, blind, keen smell & touch ■ cylindrical body, no fins, and smooth non-scaly skin, copious slime ■ can be used for leather ● Vertebrates ○ have chordate characteristics ○ integument: epidermis and dermis ○ endoskeleton - limb girdles (calcified [mineral]) ■ muscles ○ complete GI tract ○ ventral heart; closed circulation ○ well-developed coelom (eucoelomate) ○ paired kidneys ○ brain and cranial nerves ○ Body plan: head trunk, post anal tail ○ 4 clusters of Hox Genes ○ All 4 animal tissue types present ■ muscle, nervous, connective, epithelial ○ Enucleated blood cells (no nucleus) allow for more space to carry oxygen 1. Fishes (largest most diverse vertebrates) ● aquatic, gill-breathing, ectothermic vertebrates that usually have fins and skin covered with scales ● Ostracoderms - small, jawless, finless fish; earliest vertebrate fossils, filter-feeders - PARAPHYLETIC ● Agnathans - Jawless fishes (Lampreys) ○ no vertebrae (cartilaginous skeleton) ○ decimated trout populations in Great Lakes - suck body fluids (parasitic) ○ cylindrical body, no fins, and smooth non-scaly skin ○ Ammocoete - larva of lamprey (4 characteristics of vertebrates) ● Gnathostomes - Vertebrates with Jaws ○ jaw evolved from gills (arches) ○ Placoderms - early jawed, armored fishes w/ paired fins CLASS CHONDRICHTHYES - cartilagenous fishes ex: sharks (shark finning), skates, rays -fast open sea predators -skeleton made of cartilage- lighter, more flexible than bone -5-7 gill slits on each side of head -ovoviviparous- lay eggs, mature inside cavity, exit mother alive -no operculum (=bony flap covering+protecting gills) -body covered by placoid (toothlike) scales
More Less

Related notes for BIOL 1115

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.