what is the difference between a homocercal tail and a heterocercal tail?
hetero–> two asymmetrical lobes
homo–> equal lobes (produces forward thrust without lift)
Organisms belonging to the phylum Chordata all have what 5 traits at some stage in their life?
what is a notochord?
hyrdostatic organ that does not compress, supports the body
what are pharyngeal slits?
where are the pharyngeal slits?
posterior to the mouth
what is the postanal tail?
posterior elongation of body past the anus
what is the endostyle?
involved in iodine metabolism
- needed to make thyroid hormones
what three things have endostyles?
what have thyroid glands?
adult lamprey and all other vertebrates
what do chordates include?
all vertbrates along with some primitive sea animals
what do hemichordata have?
what do hemichordates lack?
class ascidiacea
cephalochrodata
-worm like filter feeders (cilia aid)
- free swimming
-dorsal nerve chord
- pharyngeal gill slits
urochordata
chordata
evolutionary systematics
places organisms in a common category based on similarities in characteristics
radial (body symmetry)
bilateral (body symmetry)
frontal plane
bilateral body into dorsal and ventral
saggital plane
bilateral body into left and right
transverse plane
bilateral body into anterior & posterior
anterior
cranial/head
posterior
caudal/tail