Exam 6 Material (Vertebrates: Part of Deuterostome Group) Flashcards
(42 cards)
What kind of group is Craniata/Vertebrata?
It’s a paraphyletic group
What does the name Craniata mean?
It means to have a cranium
What does the name Vertebrata mean?
It means to have a vertebrate
Both the cranium and vertebrate are a part of what?
Both are a part of the endoskeleton
What is special about some members of this group?
There are living groups that have a cranium but no vertebrate
Neural crest cells during development give rise to what structures (examples)?
Structures like nerves, head muscles, parts of the cranium and jaws
What are neural crest cells derived from?
They are derived from ectoderm but migrate to weird places and act like mesoderm
What is being described?:
- We see pronounced cephalization (the head becomes much more loaded w/ sensory structures, development at the anterior and posterior dorsal hollow nerve cord to be more like a brain/they get a more elaborate brain/they get 10-12 pairs of cranial nerves)?
What is special about the head of vertebrates
How many pairs of appendages do most vertebrates alive have?
They have 2 pairs of appendages (pelvic and pectoral)
What kind of hearts do vertebrates have?
They have ventral hearts
What kind of circulatory system do vertebrates have?
They have a close circulatory system (and blood with hemoglobin)
What does the name Agnathons mean?
It means without a jaw (includes hagfish) (they do not have a vertebrate but have a cranium) (they do not have jaws but have a mouth)
What is special about the lamprey?
They have a mouth but no jaws
What is being described?:
- Will attach to a host using a raspy tongue-like structure to grind a hole in the animal and suck out blood and other nutrients/they do not have paired fins)
How parasitic lamprey attack host
What kind of group are the jawless fishes?
They are a paraphyletic group
What kind of group are jawed organisms?
They are a paraphyletic group
What does the name Chondrichthyes mean?
The name means “cartilage fish”
What group includes sharks and rays?
Chondrochthyes
What makes the skeleton of Chondrichthyes special?
They have a cartilage-based skeleton
What are almost all Chondrichthyes?
They are almost all marine (w/ only some freshwater individuals like stingrays)
Does Chondrichthyes have paired fins?
Yes, they do have paired fins (anterior and posterior)
What do sharks and rays have (are essentially teeth/they have enamel) (their entire body is covered with teeth/dermal denticles)/there are continually making new teeth (when teeth break off, teeth from the back move up to replace them)
Placoid scales
What do sharks and rays not have to help them maintain their buoyancy in the water?
They do not have gas ladders (one way that they do maintain their buoyancy is through a fatty liver) (also they have wing-shaped fins that give them a lift)
How do some sharks and rays feed?
They are filter feeders (open their mouths, let food flow through—are not big predators)
