MIDTERM 2 Flashcards
Describe Flatworms
Platyhelminthes
- no respiratory/circulatory system
- digestive cavity has 1 opening
- simple nerve nets, most neurons in head (ventral)
- have sensory receptors in head-light and smell, but no eyes or organized sensory organs
- free living mostly predators (some parasitic eg tapeworms and flukes)
Who is trochophore larva
Annelida
What is protosome and who is is
bilateral, 3 germ layer, first opening is mouth
flatworms (platyhelminthes)
Describe Ribbon Worms
Nemertea
- less than 20cm long
- have probiscis used in hunting, stored in digestive cavity (stylet)
- simple brain and pair of ventral nerve cords
- simple circulatory system - coelems, no gills-respire thru skin
- separate sexes-broadcast spawners
- most benthic (inc. deep sea), some pelagic
- parenchyma
What is deuterostome and who is it
first opening is anus, nemertea (ribbon worms)
Describe Round worms
Nematoda
- small, often meiofauna, adults 0.1-3 mm
- 1 sq meter of bottom mud can contain >1 million nematodes
- more than 5,000 species
- scavengers, nutrient turnover (consume detritis bacteria-some carnivores, parasites)
- no gills, simple fluid circulation
- no circular muscles
Describe Segmented worms
Annelida
- bristle worms, christmas tree worms, hot vent tube worm
- includes all segments worms (polychaetes, earthworms, leeches)
- complex shared circulatory system of many organs, inc. simple gills (terrestrial via skin)
- complex shared circulatory system, gut and nervous system sensory organs
- body wall of collagen-a protein-can grow Chaeta (chitonous bristle) made of beta-chitin
- up to 10ft long
- soft bodies
unique features of tube worms
have no gut, and gain nutrients from chemotrophic bacteria living inside them
unique features of christmas tree worms
filter feeders, use palps as structure food harvesting and respiratory structures
feather like structure of palps called radioles
describe bryzoans
- filter feeders-use crown of lophophore tentacles
- colonial - made up of zooids
- autozooids- feeding and excretion. other specialize in reproduction, defense, even locomotion
- cause disease in kelp
- eaten by many grazers, nudibranchs urchins
described generalized autozooid
digestive tract, retractor muscle, gonads, and outer covering
Who are hagfish
Myxini
Who are lampreys
petromyzontida
Who are cartilaginous fish
chondrichthyes
Who are ray-finned fish
actinopterygii
Who are colecantis
actinistia
Who are lung fish
Dipnoi
describe lampreys oral area
have oral disk and rasping tongue covered with horny dentacles to grasp prey, rasp hole in the bosy and suck out tissue and fluid
describe lamprey reproduction
anadromous (return to fresh water to spawn) but males do not return to natal stream
males migrate up rivers and build nests, females arrive and attaches to the nest stone with oral sucker, male attaches to back of females, eggs and sperm shed
what are lamprey larva called and describe them
ammocoetes, benthic, filter feeders, after 3-7 years they metamorphose into adults and return to sea
describe the fin names
small/front-pectoral left medium-pelvic right-dorsal left-anal back-caudal small back-adipose, or 2nd dorsal
describe cartilaginous fish
sharks, skates, rays, and chimaeras
skeleton of cartilage
posses jaws and paired fins
placoid covers skin
what are the two main groups of cartilaginous fish
Holocephalans- chimaeras, or ratfish
Elasmobranchs- 2 body forms: streamlined eg sharks or dorsoventially flattened eg skates and rays
list some holocephalans
rat fish, longnose chimaeras, elephant nose chimaeras, plough nose chimaeras
describe chimaeras
large pointed head & long slender tails
gills covered by operculum, water inhaled thru the nostrils rather than mouth
have flat plates for crushing prey instead of teeth
scales confined to a few dentacles, if they have scales they are placoid
-no cloaca is have seperate anal and urogenital openings
males have claspers on their heads and pelvic fins
describe who has each type of scale
ctenoid-bass
cycloid-salmon
ganoid-gar
placoid-shark
describe reproduction in chimaeras
oviparity; fertilization internal, lay eggs, embryo has a yolk sac for nutrition
ovoviviparity; fertilization internal, eggs hatch internally, embryos feed off yolk sac and uterine milk (mammals have viviparity utilizing placentas)
list elasmobranches organisms
sharks & rays, ground & requiem sharks, mackerel sharks, carpet sharks, angel sharks, bullhead sharks, saw sharks & saw fish
describe ground/requiem sharks
order carcharihiniformes (tiger, hammerhead, bull shark, black tip, blue) nictitating membrane (third eye that is translucent/clear) 2 dorsal fins, 1 anal fin 5 gill slits
describe mackeral sharks
order lamniformes (great white, thresher, basking)
no nicitaitng membrane
2 dorsal fins, 1 anal fin
5 gill slits
describe carpet sharks
order orectolobiformes (whale, zebra) 2 dorsal fins, anal fin 5 gill slits
describe angel sharks
(austrialian)
2 dorsal fns, no anal fin
ovoviviparous
describe bull head sharks
small spiracle (port jackson, horn)
2 dorsal fins with fin spines
anal fin
oviparous
describe saw sharks and sawfish
5/6 gills
2 dorsal fins no anal
2 barbels on saw
characteristics of saw sharks and sawfish
- cartilage skeleton
- some 2 some 2 dorsal fin, some have dorsal spines
- most have accessory, respiratory opening, the spiracle
- can breathe via ram or buccal pumping
- placoid scales
- liver contains squalene - an oil
- modified pelvic fin in males, claspers
describe skates and rays
gill slits on ventral surface
no anal fin
pectoral fins usually fused to top of head
eyes and spiracles on top of head (specialized gill slits located behind eyes)
all skates and some rays are oviparous, other rays are ovoviviparous (aplacental)
stingrays and relatives (eagle, manta)
