The flashcards below were created by user
on FreezingBlue Flashcards.
What type of group are invertebrates?
How do sponges feed?
- Suspension feeders
- engulfed through phagocytosis
- choanocyte digests nutrients
- amoembocyte transport nutrients
How do sponges reproduce?
- sequential hermaphroditism (born one sex but change at some point in life)
- sperm is a modified choanocyte
- egg is a modified amebocytes
- larva stage is ciliated
Importance of Sponges
- filter feed and therefore clean water
- home for other organisms
- mutualism with single-celled algae
Human uses for sponges
- antibiotics and anticancer drugs
- bath and art sponges
- (most organisms don't eat, toxic)
Characteristic of Phylum Cnidaria (jellyfish, hydras, sea anemones and coral)
- Eumetazoa (includes most animals other than sponges): have true differentiated tissues
- -diploblastic= two layers (endo & ecto)
- Mostly radially symmetrical
- Almost entirely marine
What are the two body forms of Cnidarians? (jelly fish, sea anemones etc.)
- Polyp: oral end facing upwards and attached to substrate (sea anemones & hydra)
- Medusa: oral end downwards, move freely through water (jellyfish)
How do Cnidarians capture prey?
Use Cnida (within cnidocyte, usually a nematocyst) for prey and capture
when cnidocyte touches something cnida shoots out and captures/poisons prey
How are classes of Cnidaria differentiated?
Dominant body form
What is the most common class of Cnidaria?
Class Hydrozoa (poly and medusa in life cycle)
alternate between sexual and asexual, but always remain diploid
- Polyp-reproduce asexually through budding
- Medusa-produced asexually but reproduce sexually, larva returns to polyp
What form is class Scyphozoa?
Mainly medusa (jellyfish)
What form is class Cubozoa?
- medusa dominant (box jellies)
- extremely toxic
What form is class Anthozoa?
- only polyps
- single-sea anemones
ecology of cnidarians
- predatory (of zooplankton)
- house symbiotic algae
- produce dangerous toxins
Importance of cnidarians
- reefs provide food and shelter for marine species
- human: tourism, fishing and aquarium trade
- coral bleaching signifies ecological meltdown
Features of clade bilateria
- bilateral symmetry
- Differentiation of head region:
- -anterior concentration of neural ganglia (brain)
- -reduced in sedentary animals
Features of Phylum Acoela ("worms")
- mostly marine worms
- no body cavity (acoelomate)
- minimal cephalization (no brain)
- use endocellular digestion since they lack anus and gut cavity