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12 Cards in this Set

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  • Back
What are the synapomorphies of Ornithodira?
Advanced Mesotarsal ankle
What are the synapomorphies of Dinosauria?
1. 3 or more sacral vertebrae
2. greatly reduced fibula
3. 3 or fewer phalanges on 4th digit of hand
What are the synapomorphies of Pterosauria?
Presence of wing, supported by 4th finger
What are the synapomorphies of Tetanurae?
What were characteristics of Pterosaurs?
Extra phalanx in digit 4, thin-walled hollow bones, large sternum, bipedality, largest was Quetzalcoatlus.
What is the function of the carina in bats?
keeps muscle from collapsing on itself during contraction so air channels are kept open
What do ova develop from?
primordial germ cells that have migrated into germinal epithelium.
What is the theca?
layer of medulla cells that is formed around the follicle cells
what is the antrum?
In Theria, a fluid-filled space between the ovum and follicle cell layer
where are sperm cells produced?
Spermatic ampullae(fish + amphibians) or seminiferous tubules (amniotes)
In what organisms are the testes unpaired? Paired?
Unpaired in agnathans, paired in gnathostomes
What is the path of sperm in gnathostomes?
rete testes to efferent ductules eo epididymis to sperm duct