Marine Biology: Marine Invertebrate Investigation

Notes from your classPresentations on 2/22

Characteristics of major marine phylums

Table of Contents:

Slide One - IntroSlide Two - Table of ContentsSlide Three - PoriferaSlide Four - CnideriaSlide Five - CnideriaSlide Six - CtenophoraSlide Seven - MuluscaSlide Eight - AnthropodaSlide Nine - EchinodermataSlide Ten - Marine WormsSlide Eleven - Marine Worms

Porifera 5000 speciesspongesmarine creatures150 fresh watersimplest cellular organization

o no symmetrysystem of pores and channels for water to pass throughsexual and asexual reproduction Three main structures

o Tubeo Tube, but biggero Big, complex

CnidariaJellyfishNo body cavityAsexualDevelop into sexual adultsSting – bees of the sea

o Special cellso Neural toxins

Four classeso Jellyfisho Box jelly fisho Hydroidso Sea anemones.

Radial symmetryCentral nerve netEat, plankton, other jellysPredator: sea turtles, ocean sunfish, rock fishMay be eaten by humanCoral and sea anemones

o Reproduce by budding or sperm in water (eww…)o Eat plankton, fisho Predators: humans

No brains! Four primitive structuresBox Jellyfish has 24 eyes200 feet long (Lions Mane) to a few centimeters in size

Cnidaria continued

CtenophoraComb JellysNot really jellyfish, but they look similar

o Lack nitokites?8 rows of cilia “comb rows”“Sea Gooseberry”Pleurobrachia pileus2 cm in size, maxno real mouths, ‘oral lobes’ insteadeat copepods, larvae, smaller planktonReflect light off of conesClose to surfaceTwo layers of skin

o Protective slim from glandsFood goes in and out the same way (gross!)Tentacles to catch prey (no sting, but sticky)Hermaphrodite: both male and female sex organs.

Mullusca Mollusks are diverseLatin for softSquids and octopusSnails and clams have a hard shell, soft insideFound in all habitats, ecologically successful. Freshwater and landHeart, gonads, kidney organsNormal digestive tract form mouth to anus (butt hole)Soft body is shared trait of all mollusks8 classes

o Gastropods: snails, sea slugso Clam, mussels, scallops, oysterso Cephalopods: Squid, octopuso Three other classes (fossilized)

160,000 known speciesContinue to grow and expand because they can adapt wellFossilize well because of hard shell.

AnthropodaArthropod, Greek for ‘joint’Segmented bodyApendage at each joint, connecting to bodyVentral nervous systemDorsal heartExoskeleton Larges phylum: 10 million speciesLots of habitats: salt and fresh water, and land12 foot leg span in larger size, or as small as planktonfeed, sense, and defend with appendages

Ghost crab (Ocyprode quddrata) or Sand Crab, dig and move up to 10 mph, sharp 360 degree vision.

EchinodermataSand Dollars and Sea cumbersInternal, water filled canalsFive-fold symmetrySand Dollars move when they are alive, moves water past mouthExternal fertilize 7000 current species10,000 extinctPredators: Star Fish

Marine wormsAnnelida segmented worm family 15000 speciesBody cavity is unique to this phylum Closed circulatory system in each segment,

can operate independentlyDigestive tract from mouth to anus Bristles along the body, marine worms have Polychaete

(Large Bristled in Latin)o Used for movement and respiration

Land worms descended from marine wormsSome drift like plankton

Sense organs and jaws on some worms1 mm to 3 m longsexual or asexual reproductionhydro thermal vent environmentsburrowed in coral reefs Tube Worm: colorful, on coral reefs, large groups,

eat brine shrimpPeanut Worm: gross, eat rotifers Predators: crab, fish, other crustations (crabs, lobsters)

Marine Worms continued