Tunicates

1
Tunicates Echinoderms

• Read 572-582
• Turn in Fruit lab by end of day
• NR 4 due by end of day

2
Echinoderms

• Contain spiny skin
• Radial symmetry
• Endoskeleton
• Water-vascular system
• Watch
• You may know examples such as sea stars and sea
  urchins

3
Water vascular

• A water vascular system allows echinoderms to
  move, obtain food, and exchange gasses.
• The water vascular system is a network of
  fluid-filled tubes including
• Ring canal
• Radial canals
• Ampullae
• Tube feet

4
Anatomy

• Ampullae- muscular sacs that force water into the
  tube feet.
• Tube foot- a hollow tube that may have a suction
  cup bottom.

5
Reproduction

• Echinoderms reproduce sexually. Gametes are
  released into the water and the resulting larvae
  swim freely for 2 years before developing into
  mature echinoderms.
• However, some are able to reproduce asexually by
  regeneration.

6
Major classes

• Milestone(s) Coelom, Deuterostome
• Holothuroidea- table 1
• Echinoidea- table 2
• Asteroidea- table 3
• Ophiuroidea- table 4
• Crinoidea

7
Milestones

• Coelom- the fluid-filled cavity in the middle of
  smaller animals.
• Deuterostome- when the blastopore develops into
  two openings (a mouth and anus)

8
Tunicates

• A subphylum of chordata.
• Chordates are organisms with spinal cords
• (well get back to them in a few weeks)
• Tunicates are unique because they have spinal
  cords but no backbones unlike familiar chordates
  (frogs, fish, birds, mammals)
• Watch
• Common example Sea Squirt

9
Anatomy

• Dorsal hollow nerve cord- runs from the anterior
  to posterior with the anterior end forming a
  brain.
• Notochord- a firm but flexible rod that supports
  the nerve cord.
• Gill slits- paired openings near the pharynx
  (like a throat)

10
Reproduction

• Tunicates are hermaphroditic. Eggs are kept in
  the body while sperm are released into the water.
• Larva resemble tadpoles.
• Like Cnidaria, larva attach to a rocky/hard
  surface and become sessile.
• Uniquely, at this stage they devour their own
  brain.

11
Major Classes

• Milestones notochord, dorsal nerve chord, gill
  slits
• Ascidiacea- table 5
• Thaliacea- table 6
• Appendicularia- table 7
• Sorberacea

12
Phylum Class Exploration

• Each table has been assigned a class from either
  echinoderm or tunicate.
• In the next 20 minutes collect the following
• 1 sample species, both common name and binomial
  nomenclature
• 5 pictures of organisms in that class
• What makes that class different from other
  classes in the same phylum.