Topic 4: Animal diversity Flashcards
(20 cards)
What are the 3 elements of biodiversity?
- Ecological diversity
- Genetic diversity
- Organismal diversity
What are the 4 ways in which evolutionary relationships are studied?
- Paleontological evidence
- Anatomical similarity
- Developmental similarity
- Molecular similarity
What does monophyletic mean?
Come from a single ancestor
What is the single ancestor of animals?
Choanoflagellate
What are the 4 key branch points in animal evolution?
- Gastrulation vs no gastrulation
- Radial vs bilateral symmetry
- Mouth vs anus formed first
- Ecdysis vs no ecdysis
What are the 3 main features of the Parazoa?
- Asymmetrical
- No gastrulation
- No true tissues
What are the specialist feeding cells of Parazoa?
Choanocytes
What are the 2 main features of the Radiata?
- Radial symmetry
- 2 tissue layers (dipoblastic)
What are the 4 main features of the protostomes?
- Mouth forms first from blastopore
- Spiral cleavage
- Early cell determination
- Body cavity forms from mesoderm
What 2 groups does the protostomes break into?
- Lophotrochozoa
- Ecdysozoa
Which phyla are included in the lophotrochozoans?
- Flatworms
- Segmented worms
- Molluscs
Which phyla are included in the ecdysozoans?
- Roundworms (nematodes)
- Arthropods
Which animals are arthropods?
- Spiders
- Insects
- Crustaceans
What are the 4 main features of the deuterostomes?
- Radial cell cleavage
- Cell fate determined later
- Body cavity forms from endoderm
- Anus forms first from blastopore
What are the 5 main features of the echinoderms?
- Water vascular system
- No brain=sessile
- Usually 5 arms
- Adults radial symmetry, larvae bilateral
- Endoskeleton made of calcareous plates
What are the 4 main features of the chordates?
- Notochord
- Dorsal hollow nerve chord
- Pharyngeal slits
- Muscular post-anal tail
Which 2 groups does the deuterostomes split off into?
- Chordates
- Echinoderms
Which group do vertebrates come from?
Chordates
What are the 4 main features of vertebrates?
- Vertebral column forms main axis of the body
- Well developed brain and sensory organs in the head
- Closed circulatory system with ventral chambered heart
What are the 3 types of skeleton?
- Endoskeleton
- Exoskeleton
- Hydrostatic skeleton
