Simple Invertebrates

Is a snake an invertebrate?

Characteristics Have no backbone Includes sponges Cnidarians (jellyfish) Flatworms Roundworms, segmented worms and mollusks (clams)

Sponges

Sketch Label top opening, flagella, body, pore

Sponges Are called FILTER FEEDERS because they take in dirty water and excrete clean water Use hairs called FLAGELLA to keep water moving through the sponge

Sponge Reproduction Asexual: use budding to grow an exact clone on their body Asexual: use regeneration to grow back body parts Sexual: use egg and sperm which combine to form larva

Sessile An organism that stays attached to one spot its entire life.

Flowers of the sea?

CNIDARIAN Jellyfish, Sea anemone, coral, hydra Sketch and label with tentacle and mouth

Heniochus acuminatus eating jellyfish

Sea anemone eating a jellyfish

This turtle thought the plastic bag was a jellyfish… he will probably die

Jellyfish Catch prey with stinging tentacles Sexually : use sperm and egg which combine to form larva

Jellyfish life cycle

Hydra Sketch, label tentacles, top opening

Hydra Catch prey with tentacle

Hydra Reproduce asexually by budding Describe: baby grows on parent, drops off

Invertebrates are not plants b/c They eat for energy Do not have chlorophyll

Radial Symmetry Body parts the same around a central point

Bilateral symmetry Body parts same on 2 sides of a line

Asymmetry No line of symmetry

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Flatworms Bodies are soft Examples are planaria and tapeworm Most are parasites, which lives on a host and harms it

Planaria Body: flat, triangular head Eat dead meat and plants Live in fresh water Move with cilia Reproduce by splitting in two Hermaphrodite: both male and female in the same body

Tapeworms Attach to host with hooks or suckers Gets digested food from host

Roundworms Found in soil, animals, plants, fresh water, and salt water (everywhere!!!!) Humans catch them by walking barefoot through contaminated fields

Roundworm mouthparts

Tick into skin, acting as a vector

Very graphic picture coming up

Guinea worm Dracunculiasis

Pinworm

Trichinella can be prevented by cooking meat thoroughly There is no cure

Dogs get heartworm by mosquito bites We call the mosquito a vector

Lumbricus terretrius

Anterior Above the waist

Posterior Below the waist

Dorsal On the back side

Ventral Belly side

#1 Setae 4 pr/segment…Bristles for movement (no skeletal system)

#2 Mucous Keep skin wet for respiration…No lungs (no respiratory system)

#3 Segments Movement… Holds organs in place Muscular system

#4 4a) Brain 4b) nerve cord Color same color Senses…Sends signals to organs Nervous system

#5 Mouth Ingestion Digestive system

#6 Pharynx Swallowing Digestive system

#7 Crop Stores food Digestive system

#8 Gizzards Grinds food Digestive system

#9 Intestine Digests and absorbs food into circ system Digestive system

#10 Anus Excretes castings (good fertilizer) Digestive system

#11 Aortic arches or hearts Color reddish Pumps blood Circulatory system

#12 Dorsal and ventral blood vessel Color reddish Takes blood to rest of body Circulatory system

#13 Nephridia 2 per segment Filters liquid waste, excretes it thru skin Excretory system

Worm Grunting To get worms to the surface, act like a mole Click here Why does it work? Click here