deuterostomia Flashcards
chrodates characteristics
- notochord
- dorsal hollow nerve cord
- pharyngeal (gill) slits
- postanal tail
phylum echinodermata
- WATER VASCULAR SYSTEM !!!!! – use to breath, move appendages, and aid in digestion
- pentaradial symmetry (body composed of 5 equal parts)
- larvae - bilaterally symmetrical
- adult - radial symmetry
water vascular system !!!
6
madreporite –> stone canal –> ring canal –> radial canal –> ampullae –> tube feet
star cellular development
4
- fertilized egg undergoes cell division (cleavage)
- embryo becomes a hollow ball of cells (blastula)
- cell pinch inwards (archenteron) during the gastula phase
- opening of the blastopore is the archenteron (digestive tract)
class asteroidea
3
- 5 arms
- tube feets
- predators or scavengers
ex. sea stars
class ophiuroidea
4
- more slender arms
- tube feets that tend to lack suckers
- move by pushing and wrapping themselves to things
- predators, scavengers, or suspension-feeding
ex. brittle and basket stars
class echinoidea
4
- ridgid endoskeleton - test
- lacks arms but has movable spine
- sea urchins are opportunistic omnivores
- sand dollars are scavengers and suspension feeders
ex. sea urchins and sand dollars
class holothuroidea
4
- saclike body
- reduced ossicles
- tentacle-like tube feet for suspension-feeding
- can eviscerate (expel insides)
ex. sea cucumber
class crinoidea
4
- attach to hard rock bottom
- filter feed
- juvenile form - sea lilies
- adult form - feather stars
ex. crinoids (only extant ones)
chordata phylum
all vertebrates are chorodata but not all chordatas are vertebrates
have 4 main characteristics
subphylum urochordata
3
- distinct larval and adult forms
- larvae are free living and have all of the chordate characteristics. bilateral symmetry
- adult tunicates tend to be sessile
ex. sea squirts
subphylum cephalochordata
4
- segmented, fishlike animals
- shallow marine waters
- have all of the chordata features as an adult
- no jaws, fins, sense organs, or developed brain
ex. lancelets
subphylum vertebrata
3
- cranium
- bony or catilaginous structure w/ brain
- vertebral column (replaces the notochord)
class cyclostomata
made up of petromyzontidas (lampreys) and myxinis (hagfish)
- agnathans (w/o jaws)
class chondrichthyes
chondro - cartilage
ichthys - fish
- have an endoskeleton rather than bone
- ampullae of lorenzini – organs that detect weak electrical fields produced by other organisms
- elasmobranchs (sharks)
- chimaeras (cartilaginous fish- ghost sharks)
class actinopterygii
ray-finned fishes
most speciose class of vertebrates
endoskeleton w/ bone
class sarcopterygii
lobe-finned fish
- actinistia (coelacanths)
- lungfishes (dipnoi)
- fins sustain weight
- moved to terrestrial lands
class amphibia
invaded land but depend on water for rep
sauropsida
amniotic egg makes them not depend on water
- amniotic egg contains an amnion (fluid-filled cavity to protect the embryo)
- yolk sac - nutrients
- shell
INCLUDES BIRDS
- clade reptilia
class mammalia
- mammary glands
- hair
- specialized teeth
- enlarged skulls
mammalian dentition
incisors - cut flesh
canines - grasp prey
premolars - tear food
molars - crush food
carnivores dentation
large canines for piercing flesh
carnassials (modified molars) shearing meat off bones
herbivores dentation
large incisors to nip and broad
flat molars for shredding vegetation
omnivores dentation
more generalized dentation to appeal for meat and plant
insectivores and piscivores
all teeth appear similar
carnassials
modified molars in carnivores
pentaradial symmetry
body composed of 5 equal parts
in echinodermata
test
rigid endoskeleton in class echinodeia
eviscerate
when they expel their insides
holothuroidea
