lecture 22 Flashcards
1
Q
Animals cells
A
- Eukaryotic (nucleus and organelle surrounded by membranes)
- specialized to perform specific functions
2
Q
Characteristics of animals
A
- Ingestive heterotrophs (plants, animals or both)
- ability to move from one place to another
- respond quickly and appropriately to changes in the environment (nervous and muscle tissue unique to animals)
- sexual reproduction
3
Q
Choanoflagellates
A
- Common animal-like protist ancestor:
Similar to choanoflagellate (unicellular, ingestive heterotroph)
4
Q
Ancestor of the animal clade
A
Probably a colonial flagellated protist
5
Q
What happened in a colonial flagellated protist that led to larger, more complex animals?
A
- Functional specialization of cells in the colony arose
- cells continued to differentiate
- multicellularity evolved
- coordinations among cells improved
- eventually leads to larger, more complex animals
6
Q
sponges
A
most ancient animal group living today
7
Q
triploblastic (evolution of true tissues)
A
3 layers:
- ectoderm
- mesoderm
- endoderm
8
Q
ectoderm
A
- ecto = outside
- skin and nervous system
9
Q
endoderm
A
- endo = inside
- gut (digestive tract)
10
Q
mesoderm
A
- middle
- muscle and connective tissues
11
Q
bilateral symmetry
A
occured along the evolution of the head
12
Q
cephalization
A
- evolution of the head
- concentration of sensory organs on the anterior end of the body
13
Q
triploblastic animals
A
have body cavitu
14
Q
coelom
A
- true body cavity
- derived from mesoderm
15
Q
coelomates
A
- animals that possess a true coelom
- bilaterally symmetric
- three embryonic tissue layers
