bio 122L - animal disections

phylum mollusca

• primarily aquatic

• either marine or freshwater

• basic body model:

  • muscular foot (how they move)

  • visceral mass

  • mantle

  • hard external shell

  • gills

what class of mollusks have 2 shells that open and close?

bivalves - hatchet foot (ex. clam)

• they use their foot for burrowing

• have 2 shells

• suspension feeders

• breathe using gills

classes of mollusks (defined by shape + how they use their foot)

• gastropods - belly foot

  • single shell or no shell

  • herbivores

  • radula - their teeth

  • ex: snail, slug

• cephalopods - head foot

  • well developed head with advanced eyes

  • tentacles with suckers (foot is modified into tentacles)

  • carnivorous

  • siphon

  • ex: squid

• bivalves - hatchet foot

  • they use their foot for burrowing

  • have 2 shells

  • suspension feeders

  • breathe using gills

  • ex: clams

general bivalve anatomy

general squid anatomy

phylum arthropoda

• body segmented into head, thorax and abdomen

• jointed appendages

• bilateral symmetry

• exoskeleton made of chitin, which they malt

• major groups:

  • crustaceans

  • arachnids

  • insects

• ex: crayfish

crayfish anatomy

• body: cephalothorax (fused head and thorax), and abdomen

• exoskeleton made of chitin

• rostrum: hard triangle behind eyes

• have an open circulatory system

• green-gland: excretory system

• have a pair of appendages on each body segment

• 2 pairs of antennas

• 4 pairs of walking legs and swimmerets  

grasshopper anatomy

• body: head, thorax and abdomen

• tympanic membrane: eardrum, vibrates when they hear noise

• Malpighian tubules: for excretion

• spiracles: for respiration

• if a female: will have ovipositor

what type of relationship do termites and protists have since they live in close association with one another?

• symbiotic relationship

phylum echinodermata

• strictly marine organisms

• radial symmetry as adults

• many have spines

• water vascular system used for locomotion

• endoskeleton

• ex: sea urchins, sea cucumber, sea dollar

starfish anatomy

• carnivorous

• have tube feet that extend or retract by water pressure in the water vascular system 

  • tube feet help the starfish move and capture prey

• madreporite: small, porous opening that allows for water to enter body for water vascular system

• pyloric ceca: digestive glands

• jelly like stuff in the middle: gonads, for reproduction

• ambulacral ridge + ampullae: involved in water vascular system

• dermal ossicles: part of skeletal system

what organ do starfish invert out of their body to hunt?

• their stomach

phylum chordata

• 4 basic features in development:

  • nerve chord

  • notochord

  • pharyngeal slits

  • post-anal tail

• can have vertebrates and invertebrates

invertebrate lancelet

• belongs to phylum chordata

• marine animal

• retains the 4 characteristics

jawless fish (lamprey and hagfish)

• vertebrate in phylum chordata

• has: cartilaginous endoskeleton, notochord, and pharyngeal gill slits

sharks, rays, etc.

• vertebrate in phylum chordata

• endoskeleton made of cartilage

• jaws: great for chomping on other meaty specimens

• fins: pelvic and pectoral

salmon, goldfish, etc.

• vertebrate in phylum chordata

• endoskeleton of bones

• internal air bladders for balance and buoyancy

• lateral line system

• operculum: a gill cover in some fish (the pin in the pic)

amphibians

• vertebrates in phylum chordata

• live in terrestrial and aquatic areas

• egg incased in jelly so it doesn’t dry out

• require moisture for reproduction

• most are carnivorous 

• ex: frog, toads, salamanders

frog dissection

reptiles

• vertebrates in phylum chordata

• produce eggs that have a shell

  • egg contains food and moisture

• internal fertilization

• amniotic egg that can adapt to living on land

• dry, scaly skin - protects against dehydration

• lungs

• advanced circulatory, excretory, and nervous systems

• ex: snakes, lizards, turtles, alligators and crocodiles

birds

• wings (with feathers for flight and insulation), and horny beaks

• evolutionary advance of hollowing bones

• lay eggs (amniotic)

• specialized digestive organs: crop, gizzard and stomach

• carnivorous, herbivorous, and insectivorous

• beak is adapted to the type of food that they eat

• feet 

mammals

• vertebrates in phylum chordata

• expansive group - can sly, swim, climb, burrow, run and walk

• all mammals have fur or hair, and nourish their young with milk

• have mammary glands

• adaptations reflect:

  • the animals food sources

  • their digestive tract (length of it)

  • teeth

ex: human, hippo, etc.