Lab 4: Annelids/Nematoda Flashcards
Gastrulation (Broad definition)
Turning from a ball of cells into an organism with multiple layers
Invagination
When the cells fold in on themselves, creating an inner layer and outer layer.
What is the cell called during invagination?
Blastula
Coelom (Broad definition)
Internal body cavity within mesoderm
True coelom
a coelom that is entirely lined with mesodermic tissue
Subcategory relationship between: Bilateria, Lophotrochozoa, Protostomia, Ecdysozoa and Deuterostomia
Bilateria->(Proto/Deutero)
Proto->(Lophotrochozoa/Ecdysozoa)
Lophotrochozoa: (lophophore/trochophore)
Ciliated feeding structure, larval stage
Ecdysozoa: (Ecdysis)
Molting, producing non living cuticle
Cuticle
Shell from Ecdysis
Metameric Segmentation
serial repition of similar parts along the length of an animal
Functions of Coelom (4)
Space: organ development and gametes
Hydrostatic Skeleton
Fluid can distribute nutrients
Digestive Muscles can be separate from movement.
Chaetae:
Bristles that anchor segment of annelid during movement
Parapodia
fleshy appendages that contain bristles, and are used for locomotion, respiration, defense
Annelid Class: Polychaetes
have many fleshy parapodia
Annelid Class: Oligochaeta
earthworms, only a few “oligo” ventral bristles