Lab 3: Cnidaria

Cnidaria: organization

tissue level

Cnidaria: embryonic development

dipoblast

Cnidaria: symmetry

radial

Cnidaria: skeleton

hydrostatic skeleton

Cnidaria: movement

1. hydrostatic skeleton

   1. muscles contract to create pressure and move body

Cnidaria: sensory/nervous

1. nerve net

2. light sensing Ocelli

   1. no central nervous system

Cnidaria: circulation

diffusion

Cnidaria: digestion/feeding

1. incomplete gut / GVC

2. intracellular digestion

3. extracellular digestion

4. cnidocytes for prey capture

Cnidaria: excretory

diffusion

Cnidaria: reproduction

1. both monoecious and dioecious

   1. some alternation of sexual and asexual stage

Cnidaria: respiration

diffusion

life form: polyp

anchored with mouth up

life form: medusa

free-swimming with mouth down

mesoglea

1. not a tissue layer

2. jelly-like substance

   1. provides substance for body

GVC

gastrovascular cavity

ectoderm →

epidermis

endoderm →

gastrodermis

Which life form is this?

polyp

What is 1?

gastrodermis

What is 2?

epidermis

What is 3?

mouth

What is 4?

tentacle

Which life form is this?

medusa

What is 1?

tentacle

What is 2?

epidermis

What is 3?

gastrodermis

What is 4?

mesoglea

What is 5?

gastrovascular cavity

What is 6?

mouth

each of these contains a stinging capsule (nematocyst)

cnidocytes

a stinging capsule that either penetrate, fasten/coil, or adhere; some inject toxins

nematocyst

Cell used for both prey capture and predator deterrent and hundreds or thousands may line exterior surfaces

nematocyst

What is this?

Cnidocyte

For class Hydrozoa which life stage is the most dominant

polyp (most colonial) although most produce a medusa stage at some point

How is the medusa stage for Class Hydrozoa

velum ring and no oral arms and have very little mesoglea

Which phylum and class is this?

Phylum Cnidaria Class Hydrozoa

What phylum and class is this

Phylum Cnidaria Class Hydrozoa

What is 1?

tentacles

What is 2?

perisarc

What is 3?

coenosarc

What is 4?

medusa buds

What is 5?

hydranth

What is 6?

goangium

What is 7?

hypostome

What are hydranths and goangium examples of

polymorphic colony

Feeding polyps

hydranths

asexually reproducing polyps

goangium

What phylum and class are these?

Phylum Cnidaria Class Scyphozoa

Which class are true sea jellies

Scyphozoa

Which class have a thick layer of meoglea

Scyphozoa

Which life stage is dominant for class Scyphozoa

medusa

What are these?

oral arms

Class Scyphozoa poly p stage

very reduced which buds off medusae

Which class is sessile with only a polyp stage (NO medusa stage)

Anthozoa

Which class exists as solitary individuals (e.g., anemones) or as true colonies (e.g., corals)

Anthozoa

Which class is all marine

Anthozoa

Which phylum and class does this belong to

Phylum Cnidaria Class Anthozoa

What phylum and class is this?

Phylum Cnidaria Class Anthozoa

Sea Fan (soft coral)

What phylum and class is this?

Phylum Cnidaria Class Anthozoa

Sea Pansy

What phylum and class is this?

Phylum Cnidaria Class Anthozoa

Anemone

What phylum and class is this?

Phylum Cnidaria Class Anthozoa

Coral (hard coral)

What is the difference between fire coral (hydrozoa) and true coral (anthozoa)

fire coral have rougher exoskeletons