Create an account
definition of animals
multicellular eukaryotes who are heterotrophic and develop tissues from embroyonic layers
same individual has male and female parts, generally each part still gives sperm to another
flagelleted cells for help in feeding, the COLLAR CELLS of sponges; closely resemble chinoflaggates-type of protist animals are closely related to
a set of morphological and developmental traits, integrated into a functional whole-the animal.
the concentration of sensory equipment at a body's anterior end, including the central nervous system/brain. Evolutionary trend typical of bilaterals
the germ layer covering the surface of the embryo, giving rise to the covering of the animal
a thrrd germ layer present in all bilaterals which lies between the ectoderm and the endoderm
a fluid or air-filled space separating the digestive tract from the outer body wall
development begins with spiral, determinate cleavage; coelom forms from splits in the mesoderm; and the mouth froms from the blastopore
Development is radial, indeterminate cleavage; the coelom forms from mesodermal outpocketings of the archenteron; and the mouth forms from secondary openings
4 Points of phylogeny agreement
(1) all animals share a common ancestor (2) sponges are basal animals (3) most animal phyla belong to the bilateral clade (4) chordates and some other phyla belong to the clade Deuterostomia
Sponges (Calcaea and Silicea)
sessile animals lacking tissues, suspension feeders, hermaphrodites. marine and freshwater.
corals, jellies, and hydras. radially symmetrical w/ grastrovascular cavity & ONE OPENING, either polyps or medusa. have cnidocytes w/nematocysts.
Flatworms; bilateral symmetry, aceolomates, with a central nervous system. no circulation. ONE OPENING= thorax. have flame cells/protonephridia. HERMAPHRODITES or fission
annelids/segmented worms. eat dirt for bacteria and fungi nutrition, then out the anus as castings. means "little rings"
roundworms; terrestrial and aquatic, parasitic and free living. have a touch CUTICLE coating body
most species diversity, insects, crustaceans, and arachnids. segmented exoskeleton and jointed appendages
sand dollars, sea stars, and sea urchins, aquatic, bilateral as larva but not as adults. using internal canals to pump water throughout body
a gelatinous region of the sponge separating the 2 tissue layers, where fertilization occurs
both ployp and medusa stages in cnidarians; polyp stage often colonial (only one to include some freshwaters, all else marine) EX OBELIA
typical flatworm, one opening is thorax, has light sensitive eyespots and lateral flaps which detect specific chemicals. NOT a parasite
class of molluscs including snails and slugs, have a spiraled shell into which the animal can retreat when threatened. marine, land and aquatic.
class of gastropods with a shell divided into two halves. no distinct head, no radula, trap food particles in mucus. can have many eyes. clams, musscles, and scallops
class of gastropods, active predators with tentacles, shell is reduced and internal. feet are at the head. only molluscs with a closed circulatory system and good sense organs, complex brain. have camera type eye.
vectors of many disease, used to drain blood. have bladelike jaws to slit the skin, use hirudin to stop blood coagulating near incision
roundworms which transport nutrients through fluid in the pseudocoelom and reproduce sexually
means "jointed feet", have segmented bodies, a hard exoskeleton, and jointed appendages. Evolved in the sea and later lived on land.
Arthropod circulatory & respiratory system
open, fluid called hemolymph is pumped by heart through short arteries and into sinuses. Specialized gas-exchange organs have evolved, most aquatics have gills and insects have tracheal systems
think fangs, they have a chelicerae, an anterior cephalothorax anda posterior abdomen, lack antenna. 8 legs
a pair of appendages functioning in sensing, feeding, or reproduction; and 4 pairs walking legs
terrestrial arthropods with mandibles, among the earliest on land, include centipes and millipedes
marine and freshwater, only arthropods w/ 2 pair antennae, large species have gills, small respirator across membrane,
"spiny skin", prickly from skeletal bumps and spines, have unique water vascular system branching into tube feet. marine
Please allow access to your computer’s microphone to use Voice Recording.
Having trouble? Click here for help.
We can’t access your microphone!
Click the icon above to update your browser permissions and try again
Reload the page to try again!Reload
Press Cmd-0 to reset your zoom
Press Ctrl-0 to reset your zoom
It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.
Please upgrade Flash or install Chrome
to use Voice Recording.
For more help, see our troubleshooting page.
Your microphone is muted
For help fixing this issue, see this FAQ.
Star this term
You can study starred terms together