Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
-fluid-filled internal body cavity
-organisms having this characteristic |
-coelom
-coelomates |
|
|
"first mouth"--animals in which the mouth arises from the blastopore--includes molluscs, annelids, and arthropods
|
protostomes
|
|
|
"second mouth"--animals in which the anus arises from the blastopore--includes echinoderms, protochordates, and chordates
|
deuterostomes
|
|
|
dividing embryo cellds are offset from one another
|
spiral cleavage
|
|
|
dividing embryo cells are aligned
|
radial cleavage
|
|
|
--process in which the ball of cells indents and grows inward
--opening of the indentation |
-gastrulation
-blastopore |
|
|
--the body cavity is formed from a solid sheet of mesodermal cells splitting
--the body cavity is formed from outpocketings of the gut that pinch off |
--schizocoely
--enterocoely |
|
|
mechanical structure in which the outer wall encloses a fluid core
|
hydrostatic organ
|
|
|
remnant of the notochord in adult mammals with a full vertebral column--a small core of gel lying between vertebrae
|
nucleus pulposus
|
|
|
part of digestive tract immidiately posterior to the mouth
|
pharynx
|
|
|
blocks of muscle
|
myomeres
|
|
|
aquatic, free floating lifestyle, often planktonic
|
pelagic
|
|
|
life on marine substrate, adult protochordates consist mostly of this type
|
benthic
|
|
|
retention of larval characteristics in the adult (two terms)
|
paedomorphosis (neoteny)
|
|
|
branch of protochordates with pharyngeal slits, dorsal nerve cord, but no notochord or postanal tail
--includes enteropneusta (acorn worms) and pterobranchia |
hemichordates
|
|
|
group that includes hemi-, uro-, and cephalo-chordates
|
protochordates
|
|
|
larvae of hemichordates
|
tornaria
|
|
|
sexual characteristic in which sperm and eggs are produced in the same gonad
|
protandrous
|
