Scribe Post 2/27/12

Today in Class...

-Turned in the isopod lab

-Starfish dissecting lab- UP 63-66

-Watched a video about invertebrates

Starfish Lab

Starfish are a part of the Echinodermata Phylum

-echin means prickly

-derma means skin

Starfish feel prickly and squishy

Parts of Starfish- what we looked for

Dorsal View

Central disc- center of starfish

Rays- "arms" usually five

Madreoporic plate- small yellow or red structure on central disc

Spines- hard, covers everything, part of exoskeleton

Aye spot- tip of each arm

Anus- opening in center of central disk

Ventral View

Mouth- center of central disk, surrounded with spines

Ambulacral groove- groove along center of rays

Tube feet- at tips of ambulacral groove, help with movement

After snipping of the tip of one ray, there is a gland called the pyloric cecum - part of digestive system

There are 5 in a starfish

Starfish have separate sexes,

testes are gray, ovaries are orange- but it is hard to tell in preserved starfish

There are 5 paris of gonads in a starfish

They have 2 stomachs

The mouth is on the ventral side- above stomach

The anus is on the dorsal side-under stomach

Water vascular system- Madreoporic plate and anything connected to it

Tube feet- suction cups, help starfish move and hold prey

Ampullae- connected to a tube foot, pink and bulblike

5 Radial Canals- inside ambbulacral groove, long hollow tube that is connected to all other radial canals through ring canal

1 circular canal

Human Ciculatory system is like the Starfish's Vascular sytem because they both have "canals"(blood vessels) that transport things

http://www.youtube.com/watch?v=pMAFZgiQ5OM&feature=related

Video:

Invertebrates can live without vertebrates, but vertebrates can't live without invertebrates.

Most animals are invertebrates.

Not the same video but its a good review about invertebrates:

http://www.youtube.com/watch?v=rU-pqs6gVPc

Homework:

Finish UP 63-66

Up 75-76

Nature due this Friday

Next Scribe:

Brianna