Echinodermata Flashcards
1
Q
Distinct features
A
- Endoskeleton
- Pentaradial symmetry
- Water vascular system
2
Q
Dinstinct features
Endoskeleton
A
- Made of small calcareous plate bound together with connective tissue
- Calcareous spines poke through
3
Q
Dinstict features
Pentaradial symmetry
A
Radial symmetry in 5 parts
4
Q
Symmetry in larvae
A
Larvae have bilateral symmetry
* Earliest echinoderms like had bilateral symmetry
5
Q
Distinct features
Water vascular system
A
- Locomotion, food gathering, respiration, & excretion
- Comprised of canals & specialised tube feet
6
Q
Classes
A
- Asteroidea
- Echinoidea
- Holothuroidea
7
Q
Classes
Asteroidea
* Organisms
* Nutrition
* Reproduction
A
- Sea stars
- Carnivorous
- Sexual reproduction: dioecious & external fertilization
- Asexual reproduction: Fragmentation & regeneration
8
Q
Classes
Echinoidea:
* Organism:
* Form:
A
- Sea urchins
- Dermal ossicles have become closely fitting plates which form a shell
9
Q
Classes
Holothuridea
* Organism:
* Form:
* Symmetry:
A
- Sea cucumbers
- Ossicles are reduced (soft-bodied)
- Secondarily evolved a degree of bilateral symmetry (as adults)
10
Q
Hemichordata
A
Acorn worms
11
Q
Chaetognatha
A
Pelagic marine predators (‘arrow worms”)
