urchin/mussel Flashcards
what are the three species of urchin?
franciscanus, purpuratus, droebachiensis
who said ‘ontogeny recapitulates phylogeny’, what does it explain?
Ernst Haeckel, 1834
-the similarities between humans and other animals
what is ontogeny
the origin and development of an individual organism from embryo to adult
what is phylogeny
the evolutionary history of a species
name some protostomes.
- what sort of cleavage?
- blastopore=
mollusks, annelids, arthropods
- spiral
- blastopore=mouth
name some deuterostomes
- what sort of cleavage?
- blastopore=
-echinoderms, chordates
-radial
-anus
anus
what sort of spawners are urchins?
broadcast
urchin= meiotic or mitotic development?
meiotic
when do urchin spawn?
when the conditions are right:
- temp
- food
- sperm
chemotaxis
the movement of an organism in response to a chemical stimulus (ie: urchin spawning)
cortical granule reaction
the slow block of an urchin’s egg from sperm, prevents polyspermy
how many cells develop in the blastula of an urchin?
128
what is gastrulation?
when the cells devide into the endoderm, mesoderm, and ectoderm
name the stages from an egg to a pleuteus urchin larvae?
egg, zygote, celled (2,4, 8, etc), blastula, gastrula, prism (starts to feed), early pluteus (4 arm), 6 arm, 8 arm
what time of year would you collect your Mytilus broodstock?
April-May for protected waters, pacific coast in fall and winter