bio test 2- kingdom animalia protostomes

phylogeny bilateria

are bilaterally symmetrical, divided into two groups protostomes and deuterostomes, all are triploblastic

phylum platyhelminthes

flatworms are soft-bodied animals, move by ciliated epithelial cells, developed musculature, free living and parastic (tapeworms), acoelomate

acoelomate meaning

no real body cavity, all muscle

phylum rotifera

“wheel animals” pseudocoelomates (fake cavities), complex internal organs, rapidly beating thick cilia at their heads (corona)

what is corona used for in rotifera?

transport or funneling in food

phylum mollusca

mollusks are second most diverse phylum, coelomates- bilateral symmetry, wide variety of sizes and body forms, live in many different environments,

what animals are in mollusca?

snails, slugs, clams, octopuses

where do most mollusca groups live?

remained in the oceans

how are mollusca economically significant?

delicious, pearls produced by oysters, mother-of-pearl is produced in the shells of abalone

what mollusks are pests?

zebra mussel- dreissena polymorpha, garden snails- helix aspersa

mollusk body plan

muscular foot of a mollusk is adapted for locomotion, attachment, and food capture

mantle of mollusk body plan

epidermis that covers the dorsal side of the body, forms a cavity which houses the respiratory organs and the openings of excretory, reproductive, and digestive organs, all organs together form a visceral mass

mollusks produce a…

calcium carbonate-rich shell, used for protection, some species have internalized or reduced shells

classes of mollusks

polyplacophora, gastropoda, bivalvia, cephalopoda

polyplacophora (many plates)

chitons, marine mollusks, oval bodies with eight overlapping dorsal calcareous plates, most are grazing herbivores

class gastropoda

snails and slugs, primarily marine (some invaded land), pairs of tentacles with eyes at ends

during embryological development, gastropods undergo…

torsion- mantle cavity and anus are moved from the posterior to the front, coiling- spiral winding of the shell

class bivalvia

clams, scallops, mussels, oysters, have two lateral shells hinged together dorsally, most are sessile (don’t move) filter-feeders, water circulation is mediated through siphons and rhythmic beating of the cilia on gills

class cephalapoda

active marine predators, foot- series of arms equipped with suction cups, squids have 8+2, octopuses 8, nautiluses 80-90, they have highly developed nervous systems- exhibit complex patterns of behavior and a high level of intelligence

cephalopoda

many can change color using pouches of pigment called chromatophores, many have an ink sac and are capable of expelling ink to confuse predators

phylum annelida

annelid worms always exhibit segmentation, building of body from repeated units, ceolomates

phylum annelida body

the front segments contain specialized sensory organs, a ventral nerve cord connects the ganglia in each segment with each other and the brain

phylum annelida features

move using their coelom as a skeleton- hydrostatic skeleton, exchange O2 and CO2 through their body surfaces, excretory system repeats at each segment

phylum annelida classes

polychaeta and clitellata

class polychaeta

mostly marine worms, have a differentiated head, have paired parapodia on most segments- used in swimming, burrowing, crawling, sexes are usually sperate, many live in tubes

class clitellata

earthworms- mostly terrestrial, live underground, eat their way through soil, consist of 100-175 segments with a mouth on the first and anus on the last, lack eyes and head, move through soil using chaetae (setae)- little chitinous bristles, no parapodia

class clitellata…

burrowing, soil consuming, hermaphroditic (both male and female), clitellum secretes mucus that holds the worms together during copulation, also secretes a mucus cocoon in which the fertilized egg develops

clitellata leeches

occur mostly in fresh water, usually flattened dorsoventrally, have no chaetae, medical leech (hirudo medicinalis) secretes anicoagulant

phylum nematoda

nematodes are roundworms comprising many species found in marine, freshwater, and soil habitats. are bilaterally symmetrical and unsegmented, pseudocoelomate

phylum nematoda body

covered with a flexible, thick cuticle, lack specialized respiratory organs and exchange oxygen through their cuticles

phylum tardigrada

“water bears”, pseudocoelomate, chitinous cuticle divided into plates, over 1,000 species, cryptobiosis

phylum tarigrada cryptobiosis

resistance to environmental challenges, desiccation, very low temperatures, vacuum, high pressure, and radiation. suspend their metabolic activity for years.survive the loss of up to 99% of their water content, unique proteins that replace water in their cells and protect cells and DNA from damage

phylum arthropoda

arthropods are the most successful animas- 1,000,000 species, about 80% are insects. arthropods affect all aspects of human life

arthropod morphology, all arthropods…

have jointed appendages, have an exoskeleton made of secreted chitin and protein- functions for protection and muscle attachment, limits arthropod body size. arthropod bodies are segmented- some segments are fused into tagmata (allow for specialization)- head, thorax, abdomen

arthropod morphology

open circulatory system, compound eyes- composed of independent visual units, other arthropods have simple, basic eyes or ocelli- have single lenses and distinguish light from darkness

arthropod ecdysis or molting

shedding the outer cuticle layer of exoskeleton

subphyla of phylum arthropoda

chelicerta, myriapoda, crustacea, hexapoda

chelicerta examples

spiders, scorpions, horseshoe crabs, harvestman (daddy long legs), ticks and mites

chelicerta

body is divided into two main tagmata (body groupings), chelicerae and pedipalps

chelicerata chelicerae

anterior appendages, often function as fangs or pincers

chelicerata pedipalps

posterior to chelicerae, resemble legs, used in reproduction, pincers, or sensors

crustacea

primarily aquatic organisms ( crabs, shrimp, lobsters, barnacles), have three tagmata but front two may fuse, have two pairs of antennae, three pairs of appendages for feeding, and various pairs of legs.most appendages are biramous- branch into two parts

crustacea mandibles

evolved from a pair of limbs that took on a chewing function

crustacea sex and development

most have seperate sexes. majority develop through a nauplius stage (larva)

hexapoda

class insecta, most abundant group of animals- more than half of all named animal species. primarily terrestrial

hexapoda external features

three body regions. head- pair of antennae, modified mouthparts, compound eyes. thorax- has three pairs of legs, may have one or two pairs of wings. abdomen- most major organs

myriapoda

centipedes- one leg pair on each segment, all are carnivores, eat insects, may be poisonous. millipedes- two legs on some or all segments, are largely herbivores. both have bodies with a head followed by numerous segments