Phylum EchinodermataMonday March 15th Daily Learning Objective: Students will understand the basic characteristics of Echinoderms: crinoids, brittle stars, sea stars, sea urchins, and sea cucumbers

Agenda

•Agenda▫Do Now▫Complete Pre-lab Lab 9 – Goldfish

Respiration▫Characteristics of Echinoderms – notes and

film clips▫If time: work on Vertebrate Project and/or

make sure your Invertebrate Grid is up to date

Homework

•Vertebrate Grid; Work Cited and Trading Cards due no later than Friday

•The Unit 7 Review will be posted by Wednesday

•Unit 7 Test is Wednesday March 31st.

Do Now

1) What happens to the number of heart chambers as animals become more complex?

2) What is the general trend in fertilization as animals become more complex?

3) What phylum of vertebrates were the first to be able to live entirely out of water?

Pre-lab

•Read short article about Endotherms and Ectotherms

•Complete pre-lab – make sure you complete the hypothesis with If…then…because statements

Critical Thinking

All echinoderms require oxygen for respiration but they lack a respiratory system.

As you learn about these interesting animals, figure out how they get the oxygen required for cellular

respiration to occur.

How is that linked to photosynthesis?

Basic Characteristics•Symmetry

▫All echinoderms have Radial Symmetry BUT… they develop from bilateral

larvae

•More closely related to Chordates than other Invertebrates▫Develop as deuterostomes rather

than protostomes

Basic Characteristics Cont’d• Endoskeleton

▫Ossicles of calcium carbonate attached to spines or spicules Enchinoderm = “spiny skin”

• Water Vascular System▫Water filled canals inside body

• Tube Feet▫Small extensions of the water vascular system▫Aid in – feeding, movement, respiration, excretion

Classification7,000 species of echinoderms in 6 classes

Class Crinoidea

•Examples = crinoids▫Sea lilies, and feather stars

•Minimal movement▫Some are sessile as adults =

sea lilies

•Tube feet serve as a respiratory surface

Sea Lily

Feather Star – Click Picture to See Video

Class Ophiuroidea

•Name means “snake like”

•Examples = basket stars and brittle stars

•Largest Class▫Characterized by long

narrow arms which allow quick movement

Basket Star

Brittle Star

Class Echinoidea

•Name means “spinelike”

•Example = Sea Urchins and Sand Dollars

•Rigid exoskeleton called a test▫Encloses the internal organs

▫Sea Urchin Eating

Click on the picture to view Sand Dollar Movement

Class Holothuroidia•Name Means “water polyp”

▫When their tentacles are extended they resemble the polyp form of some cnidarians

•Examples = Sea Cucumbers

•Live on the sea bottom▫Crawl and burrow into soft

sediment

•Eats by cleaning food off tentacles

Class Asteroidia

• Name Means “starlike”• Tube Feet are used in:

▫Movement▫Capturing Prey▫Gas Exchange

• Have TWO stomachs – Cardiac and Pyloric▫Digestion occurs in this orde

r:

Cardiac Stomach – Pyloric Stomach – Digestive Glands

• Remarkable Regeneration