ch. 32 Flashcards
characteristics of animal kingdom
Martha has cold numb smiles surviving every joke
1. multicellular
2. heterotroph
3. cells lack cell walls
4. have nerves, muscles, capacity to move at some point during life cycle
5. ability to reproduce sexually
6. specialized sensory structures/nervous system
7. cells exist in extensive extracellular matrix
8. unique cell junctions
main morphological/developmental features for classification
- presence or absence of different tissue types
- type of body symmetry
- number of germ layers
- presence or absence of true boy cavity
- patterns of embryonic development
para
along side
zoa
animals
what 2 subkingdoms are kingdom Animalia split in to?
- subkingdom parazoa
- subkingdom eumetazoa
metazoa
tissue of all animals
what is metazoa divided into
- parazoa
- eumetazoa
parazoa
no specialized tissues or organs
- porifera - sponges, bearing pores
eumetazoa
more than one type of tissue and organs
meta
after or along with, change
eu
true
what is subkingdom eumetazoa divided into
- diploblastic
- triploblastic
symmetry of eumetazoa
- radially symmetrical (Radiata)
- bilaterally symmetrical (Bilateria)
what do bilateral animals have
- cephalization
- dorsal and ventral ends
cephalization
concentration of sensory and feeding organs around brain/head
3 germ layers of bilateral animals
eco-, meso- endoderm
what do radial animals have
oral and aboral sides
2 germ layers of radial animals
ecto-, endoderm
lateral
side to side
cephal
head
ab
away
germ
give rise
different axes of body (think fish)
- anteroposterior axis
- dorsoventral axis
- left-right axis
- proximodistal axis
are bilateria triploblastic or diploblastic
triploblastic - 3 germ layers
are radiata triploblastic or diploblastic
diploblastic - 2 germ layers
when do cell layers develop?
during gastrulation
inner layer
endoderm
outer layer
ectoderm
3rd layer in bilateral animals
mesoderm
- forms muscles and most other organs
blast
to lay down
derm
skin
meso
middle
gastro
stomach
process from zygote to gastrula
- zygotę - cleavage
- 8-cell stage Morula - cleavage
- Blastula (hollow ball)
- gastrulation
- gastrula (with endoderm, ectoderm, mesoderm, blastopore, archenteron)
arche
old, primitive
entero
intestine
true coelom
body cavity completely lined with mesoderm (coelomates)
pseudocoelom
coelom not completely lined by tissue derived from mesoderm (pseudocoelomates)
acoelomates
lack body cavity entirely
what can a fluid-filled body cavity do
protect internal organs or be used as hydrostatic skeleton
mesenchyme
connective tissue
chymus
bodily fluid (Latin)
2 types of cleavage
- spiral
- radial
2 fates of embryonic cells
- determinate cleavage - development arrested
- indeterminate cleavage - normal embryo
2 fates of blastopore
- blastopore becomes mouth
- blastopore because anus
protostome embryonic development
spiral cleavage, determinate cleavage, blastopore becomes mouth
deuterostome embryonic development
radial cleavage, indeterminate cleavage (pluripotent stem cells), blastopore becomes anus
stome
mouth
deutero
second
how many larval stages do most animals have
at least 1
larva
sexually immature and morphologically distinct from the adult
- undergoes metamorphosis to become a juvenile
juvenile
resembles adult, not yet sexually mature
morph
shape
all animals have developmental genes that what?
regulate expression of other genes
Hox genes
unique family of developmental genes that most animals share
what do Hox genes regulate
development of body form
evolutionists and Hox genes
although Hox family of genes has been highly conserved, it can produce a wide diversity of animal morphology
Lophotrochozoa
another clade of bilateral invertebrates
lophophore
feeding structure of some lophotrochozoans
trochophore larva
distinct developmental stage of some lophotrochozoans
