1. Cell Type: Eurkaryotic
2. Cell Number: Multicellular
3. Have Cell Organization
4. Energy: Heterotrophic

95% of animals are invertebrates.

The term "invertebrate" means "no backbone."

1. Salt Water is Buoyant (helps them float)
2. Water temperature and pH (*how acidic/basic) is more constant
3. Water is isotonic to cells  (*in other words, water outside of cells and inside of cells has the same concentration or solute dissolved in solvent - water flows in and out at the same rate so cells don't shrink or expand but stay the same size)

1. Contractile Vacuoles
2. Temperature Adjustments

1. Internal or External Skeleton (like tissue)
2. Reproduction 
1. some require water
2. return to water to lay eggs
3. shells
4. internal gestation

Picture 1: Moon Jelly

Picture 2: Nomura's Jellyfish (HUGE)

1. Environment: aquatic (mostly saltwater)
2. Shape: 
1. Radial Symmetry
2. 2 forms: Polyp Stage and Medusa Stage 
3. Movement:
1. Polyp is sessile (non-moving)
2. Medusa is free-swimming

1. Mature Polyp (with feeding branch and reproductive branch)
2. Reproductive branch produces female and male medusae (free-floating stage, looks like tiny jellyfish)
3. Female Medusa makes ovum 
4. Male Medusa makes sperm
5. Fertilization = zygote
6. Zygote divides to make blastula
7. Blastula becomes Planula then develops back to Polyp again[image]

1. 2 Cell Layers - allows diffusion of oxygena and carbon dioxide respiration (*diffusion is movement of gases across cell layers)
2. Digestion: Happens in center body cavity (gastrovascular cavity)

What do the 2 pictures represent below?

What does the dark blue, space, and then yellow areas  represent?

What does the central space inside represent?[image]

Pictures show Polyp (sessile stage, doesn't move) and Medusa stage (does move)

Outside dark blue is Epidermis cell layer.  Inside yellow is Gastrodermic cell layer.  Light blue space between blue and yellow layers is the mesoglea.

Central space is the gastrovascular gavity.

1. Stinging cells
2. Capsule has wound up string with spikes
3. Capsule discharges string w/ spikes when touched
4. Releases paralyzing potion!

What class of Cnidarians is shown below?

[image]

What class of Cnidarians do the pictures show below?

[image][image]

1. ENVIRONMENT: oceans and some freshwater
2. SHAPE: assymmetrical (no shape)
3. MOVEMENT: sessile
4. FEEDING: heterotrophs

1. Two Cells layers (just like Cnidarias - epidermis outside and gastrodermis inside lining gastrovascular cavity)
2. Variety of Sponge Body Morphology (shapes)
1. encrusting sponges
2. tubular sponges
3. pecten sponges
4. boring sponges

1. Spicules - made of calcium carbonate or silica between layers of cells
2. Osculum - large opening, expels water and waste at the top of sponge