Lecture Final Flashcards
What are Anapsids?
organisms with 0 temporal fenestrae. ex. turtles
What characterizes the dermis of mammals?
exceptionally thick dermis with presence of hair follicles
What are four types of chemoreception?
- Olfactory
- Gustatory
- Pheromones
- Unspecialized (ex. crying with onions)
What is the K-T boundary/ extinction?
65 million years ago (between the cenozoic and mesozoic eras).
The cretacious-tertiary boundary was a mass extinction where 80% of animals died (including the dinosaurs), but birds and crocodiles survived.
What are three strategies of increasing surface area of the intestine?
- Caeca (extensions)
- Spiral Valve: found in sharks and lungfish; increase path length
- Foldings: found in tetrapods.
What are placentals?
Mammals with placentas. I.e. humans.
Most widespread group of living mammals.
In the eye, what is the function of the Iris?
Controls entrance of light
What characterizes cynodonts?
- changes in jaw muscles allowing chewing
- Two occiptal condyles
- Semi-erect hindlimbs
- nasal turbinates
What are the four types of fenestrae?
- Anapsid
- Synapsids
- Diapsids
- Eurapsids
What two parts does the Rhobencephalon contain? What are they composed of?
Metencephalon: cerebellum, pons (exclusive to birds and mammals)
Myelencephalon: medulla oblongata
What are the components of the middle ear?
The incus, malleus, stapes
What are the three extra-embryonic membranes of the cleodoic egg?
- Chorion
- Amnion
- Allantois
What are the components of the outer ear?
Pinna, ear canal and tempanic membrane
What is the Rhombencephelon?
Hindbrain
What are the three membranes in the vertebrate ear?
Tectorial
Basilar
Vestibular
What two branches come from amniotes?
Sauropsids and Synapsids
What are pelycosaurs?
They are extinct “reptile- like” organisms with one occiptal condyle at the back of their skull (that rotates with the vertebrae).
What is the visceral nervous system?
Smooth muscles and glands (either sensory or motor fibres).
What are the three groups of extant mammals?
- monotremes
- marsupials
- placentals
What is aves? When did they radiate?
Birds. They radiated in the tertiary (cenozoic).
What characterizes a pronephric kidney?
- segmented, first 4 segments
- appear in all vertebrates (rudimentary
form) and quickly degenerate - functional in fish larvae, adult hagfish and some teleosts
What type of evolution do bird and mammal hearts represent?
Convergent evolution. 4-chambered with similar
design, but different origin.
The absence of cardiac shunt probably was an adaptation to allow
different arterial pressure in lungs vs body in active animals.
What are efferent nerves?
Motor nerves: Sends signals from the CNS to the organs (i.e. for movement).
What is a buccal pump?
Its a positive pressure used to push air into the lungs.
Found in fish and amphibians.