unit 7 Flashcards
Phylum echinoderms
benthic animals
such as urchins, sea stars, sea cucumbers, and sand dollars, battle star
pentaradial symmetry
internal endoskeleton
water vascular system
pentaradial symmetry
five arms or fans radiating from a central body cavity
echinodermata
spiny skinned
water vascular system
network of water filled canals that extend to tube feet
have suction
used for locomotion and feeding
echinoderm reproduction
most reproduce by spawning - males and females release sperm and eggs into water collumn to be fertilized externally
develop into free difitng larvae zooplankton
ecological importance of echinoderms
crown of mornes seastar us a keystone species - feeds coral, increases biodiversity on reef
in kelp forests urchins graze intensely on kelp, keep them under control sea otters and sheephead fish
on sandy shores, sea cucumber fill water and sand releasining Nitrogen trappd in setement
Phylum anthropoda examples
largest phylum (75 percent of all animals)
all insects and araneids
all crustaceans (shrimp, crab, lobster, barnacles)
most are decapods 10 legs
anthropoda characteristics
bilatterally symmetric - mirror image both sides
joined apendages for walking
segments of body (head, thorax, abdomen)
first set of ledgs are modified into claws called cheliped
exoskeleton does not grow with animal, molts and grows larger one
carapace covers head and thorax - gills under to obtain CO2
lobster and shrimp have swimmerets extra paddle like fins
Chelipeds
crusher is larger
pincer is narrow/sharp
Crustacean reproduction
after mating, female carries fertilized eggs under abs
once developed - releases them as free-floating zooplankton - undergo stages
zoea - megalopa - juvenile - adult
cnidaria examples
jellyfish, corals, and anemones
cnidaria characteristics
radially symmetrical - similar parts repeated around central axis
centrally located mouth surrounded by tentacles - used to sting and capture food
carnivores - tentacles contain venomous called nematocysts - used to sting prey
two basic cnidaria body forms
polyps - non mobile (sessile) with mouth and tentacle facing upward
medusa - upside down polyp adapter for drifting (jellyfish)
jellyfish
limited swimming - drift with current
11 inch to 200 feet long
predators- sea turtles and fish
food- plankton or small fish
boy jellies, (ex is sea wasp a lot) fatal sting
venom of others are mild to harmless
jellfish cycle
larvae to polyp to building colony to juvenile to adult medusa
how sally lightfoot adapts to habitat/lifestyle
jumping and running to get food, not be food to eels
how coconut crab adapts to habitat/lifestyle
with large legs can crack coconuts for food and stay on rock so dont drown
how lobster adapts to habitat/lifestyle
use size to fight for shelter
crustacean ecological importance
many are scavaging species, detrivores, and play role in recycling nutrients
food sourcs
-copepods are an abundant type of zooplankton
-krill are major food source in polar waters
some copepods and isopods are parasitic to fish
other crustacceans are barnacle, copepods, isopods, krill
jellyfish reproduction
release sperm and eggs
gametes meet, fertilize, grow into larvae, settle onto hard surface, grow into a colony, grows into adults
Mollusca phylum
three-part body
foot, head, visceral mass (has organs)
some foot divided as tentacles
most mollusks have a shell to protect ahrd body
nautilis
living fossil - represent lineage of cephalopds dating 500 million years
gastropods
one shell (conchs, snails, slugs)
calcium carbonate shell is produced
use foot to propel forward
sea slugs / hares in this despite no shell
bivalves
two shells hinged together by abductor muscle (clams, oysters, scallops, mussels
filter feeders - clear water as they filter water all day
some sessile dont move
-some attach life to hard sufaces like oyster
-must spawn to reproduce
-some burrow (clams)
cephalopods
no shell (octopus, squid, cuttlefish - most intelligent invertebretes tentacles foot divided)
most have ink sac to confuse predators
some bioluminescent
beak some with venemous bite
may change color within seconds
siphon allow jet propulsion
ancestors had shells nautalis do
phylum porifera
sponges have porous body
filter feeders, filter microscopic particle and organix matter from the water that flows through bodies
reproduces by spawning or budding
provide shelter for tiny organisms
spicules provide structural support made of calcium carbonate or cilia
marine worms
all six phylums contain these
come in various shapes and sizes
ecological roles: nutrient recycling and serve as a food source for many marine creatures
