PORIFERA AND CNIDARIANS
What is the main habitat of sponges and cnidarians?
The sea/ocean
What type of symmetry do they have?
Bilateral
True or false and correct: All molluscs are aquatic
False. There are terrestrial ones such as snail and slug
True or false and correct: they are the most numerous and varied phylum of the animal kingdom, so they inhabit all environments.
True
What type of symmetry do they have?
Radial symmetry
What does mean sessile?
They live fixed to the bottom
Name the three phyla
flatworms, nematodes and annelids
Describe the general body of molluscs
- Soft and with bilateral symmetry.
- Body with outer layer (mantle) surrounding organs (visceral mass).
- Many have a shell (external or internal).
How is protected body in arthropods?
by a chitin exoskeleton
How is called their skeleton?
Dermoskeleton
Name the two different elements that can made up the internal skeleton of sponges
Spicules (rigid spines) and spongine fibers (flexible)
Indicate two characteristics of planarians
Free life worms, eye spots, fragmentation
tongue with small rigid spines that allows them to scrape or crush food.
What group can perfom metamorphosis?
Insects
How are called the structures that make possible movement in this group?
Ambulacral feet
What are cnidoblasts?
Cells that have rolled-up flagella that inject a paralysing liquid into their prey
What is the special characteristics of tapeworms related to reproduction?
They are hermaphrodites and can fertilize themselves
How is fertilization and embryonic development in molluscs?
Mainly external fertilization and oviparous
What structures do they have to breathe?
Tracheae (terrestrial ones)
Gills (aquatic ones)
Tell and example of carnivore and herbivore echinoderm
Carnivore: starfish
Herbivore: sea urchin
What is the function of choanocytes?
They generate a stream of water, which penetrates through the pores and allows them to obtain nutrients and oxygen.
How is called the thickened glandular structure of annelids involved in reproduction?
Clitelum
Clasifica los siguientes moluscos en su subgrupo correspondiente: calamar, berberecho y lapa
Calamar: cefalópodos
Berberecho: bivalvos
Lapa: gasterópodos
Classify the following arthropodos in their subgroups: barnacle, grasshopper, mite, Nautilus
Barnacle: crustaceans
Grasshopper: insects
Mite: arachnids
Nautilus: cephalopods
Explain the characteristics of reproduction in echinoderms
- Sexual reproduction.
- Mainly external fertilization.
- Oviparous.
- Starfish: asexual reproduction by fragmentation.