Zoology Test 1c Flashcards
1
Q
Porifera reproduction
A
- sexual reproduction
- broadcast fertilization
- species take in sperm from exterior and fertilize internally, larva hatched internally
- some species broadcast both sperm and oocytes
2
Q
broadcast fertilization
A
throw it out there, need a phase to be synchronized
3
Q
blastula
A
stage after fertilization that contains flagella on the inside which turns itself inside out
4
Q
what is the motile stage of porifera reproduction?
A
parenchymula larva
5
Q
How do sponges differ from protozoa?
A
- cell specialization in form and function
- coordination of different cell types
- begin to hint at tissues
6
Q
How are sponges similar to protozoa?
A
- sexual and asexual reproduction
- intracellular digestion
- no organs or true tissues
7
Q
common characteristics of Cnidaria
A
- radial symmetry
- invented movement
- germ-layers
- do have tissues
- have mouth
- have digestive cavity - extracellular digestion
- mostly marine
8
Q
significance of Cnidarians
A
- contains most primitiver members on main line of eumetazoan evolution
- fossils up to 700 million years old
9
Q
cnidarian symmetry
A
- have two ends
- oral end which is the mouth
- aboral end which is the opposite side of mouth
10
Q
nematocysts
A
- mechanism used in cnidarians
- located in the cnidocytes
- sting and paralyze prey
- entangle prey
- triggered by contact
11
Q
cnidocytes
A
specialized cell
12
Q
nervous tissue of cnidarians
A
- true tissues include nerve net
- bidirectional nerve cells
- radial symmetry means no CNS
- nerve cells connect to muscular cells forming coordinated neuromuscular system
13
Q
cnidarian body plan
A
- basic structure: digestive sac with one opening, two-way digestive system
- diploblastic
- two distinct layers: epidermis and gastrodermis
- gastrovascular cavity
- two forms: polyp and medusa
14
Q
diploblastic
A
when blastula, has two layers of tissue
15
Q
epidermis
A
outer tissue layer
16
Q
gastrodermis
A
inner tissue layer
17
Q
mesoglea
A
jelly-like layer inbetween the epidermis and gastrodermis