Class notes
Echinoderms
- Course
- Institution
Lecture notes about Echinoderms
[Show more]
Seller
Follow
seanleviabiera
Content preview
15_PHYLUM ECHINODERMATAGENERAL CHARACTERISTICS
- “spiny-skinned”
- highly-organized marine invertebrates
- coelomate
- thrives in marine environment
- primitive senses
- water vascular system
DISTINCT CHARACTERISTICS
- Calcareous skeleton (crystalline calcite)
- Non-parasitic
- Tube feet (podia)
- primitive bilateral symmetry masked by a strong 5-fold radial symmetry
ARTHOPODA SIMILARITIES ECHINODERMATA
-exoskeleton -bilaterally -skeleton enclosed in
symmetrical soft tissues
-respiratory
system -highly varied -osmotic regulation
-chitinous -calcareous skeleton
skeleton
ECHINODERMATA SIMILARITIES CHORDATA
-absence of -bilaterally -notochord
notochord symmetrical
-phosphatic
-calcite skeleton -larval stage skeleton
-tube feet -central -respiratory
nervous system
-water vascular
system
system
-body fluid
proteins
, MODE OF LIFE
GENERAL
- known only to live in marine environments, though some can be found in
brackish water
- vary from filter feeders to active predators
- filter feeders - mud passes through the alimentary tract
- no true planktonic echinoderms
CRINOIDS
- live in strong currents, such as zone of breaking waves
- shallow waters to abyssal depths
- filter feeders
- two types: stem-bearing / stalked and free-swimming
ASTEROIDS AND OPHIUROIDS
- sea stars and brittle stars
- littoral zones and deep waters
- muddy bottom
- survival mechanism: fast / slow movement
ECHINOIDS
- mobile algae grazers
- most burrow, but some use their spines or tube feet to anchor themselves
- found from intertidal zone to deep marine
HOLOTHUROIDS
- muddy bottom
- survival mechanisms
o slow creeping
▪ swimming
▪ burrowing
- tube feet
SEXUAL REPRODUCTION
- simple reproductive organs
- the eggs are released and fertilized externally
- larva is bilaterally symmetrical, is free-swimming, and lacks calcareous skeleton
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller seanleviabiera. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.49. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
79223 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now