Simple Animals Flashcards
Why are sponges and cnidarians animals?
1) multicellular
2) heterotrophic
3) have no cell wall
4) motile at some point
Difference between adult and larval sponges
Larval are more motile
Why are sponges so simple
Because they have no tissues or organs
The anatomy of a sponge
Made of two types of cells (amoebocytes that perform digestion and collar cells that move water through the organism) and spicules
How do sponges get food
The filter the water plankton or organic material
what is one advantage to having no true tissues or only a few specialized cells
Easy to regenerate
How can you classify phylum Cnidaria
1) Incomplete digestion
2) soft body
3) tentacles with stinging cells
4) no central nervous system
What is a nematocyst (cnidocyte) and what do cnidarians use them for
It’s a stinging cell to immobilize prey
What type of symmetry do cnidarians have
Radial
What are the two body types for cnidarians
Medusa an polyp
Characteristics of class Anthozoa and an example
1) Polyp entire lives
2) upward facing mouth
3) sessile
Coral, anemones
Characteristics of class syphozoa and an example
1) Medusa as adults
2) downward facing mouth
3) motile as adults
Jellyfish
Characteristics of class Cubozoa and an example
1) Medusa
2) downward facing mouth
3) box shaped
4) motile
Box jellyfish
Characteristics of class Hydrozoa and an example
1) Mostly polyps
2) upward facing mouth
3) microscopic
4) can live solo or in colonies
Hydroids
How can you tell the difference between the three types of simple worms
Flatworms have a wide, smooth, flattened shaped with incomplete digestion
Ribbon worms have a narrow, long, flattened shape with complete dig
Round worms have a short, round shape, with complete dig
All Mollusks have these characteristics
1) have a mantle
2) digestive tract has two openings
3) share similar developmental patterns
4) have a coelom (body cavity)
Some Mollusks have these characteristics
1) Hard external shell
2) bilaterally symmetrical
3) live on land
4) inhibit aquatic environments
5) are slow moving
Describe the head-foot region of a cephalopod
The muscular foot is divided into tentacle and they surround the mouth. The eyes are behind the tentacles
How does the intelligence of an octopus compared to that of a clam
Octopus can problem solve and change their appearance blend in with different environments
Characteristic of Gastropods
1) external shell
2) use radula in feeding
3) use a large foot to move
Characteristics of bivalves
1) have no distinct head
2) external shell
3 use gills for respiration and food collection
4) use a large foot to move
5) filter the water for plankton in order to feed
Characteristics of Cephalopods
1) intelligent, well developed nervous system
2) use mantle to move around
3) external shell
4) carnivores
5) use radula in feeding
6) bite prey with beak
Why did early scientists classify corals and sponges as plants
They don’t appear to move
