E3: Chordata Flashcards
Where does the name chordata come from? (What does it reference to?)
Notodord
What are the subphylums of phylum chordata?
- Urochordata
- Cephalochordata
- Vertebrata
What are the basic characteristics of chordata?
- notochord
- dorsal hollow nerve chord
- gill slits
- post anal tail
- endostyle or thyroid gland
What is the first part of te endoskeleton to appear in the embryo?
The notochord
What heppens to the notochord in protochordates and jawless vertebrates?
It persists throughout life
What happens to the notochord in vertibrates?
Cartilaginous or bony vertabrae form to replace the notochord
What does the notochord act as?
A hydrostatic skeleton
Describe the dorsal hollow nerve cord in invertebrates vs vertebrates.
Invertebrates: solid, ventral nerve cord
Vertebrates: hollow, dorsal nerve cord
How is the dorsal hollow nerve cord formed?
From in-folding of dorsal ectoderm
The cranial portion of the dorsal hollow nerve cord specializes to form the _______.
The brain
What will surround the brain and spinal cord for protection?
Bone and cartilage
Descpribe pharyngeal pouches and slits.
- openings from the pharynx to the outside
- evolved as a filter feeding apparatus
