Exotic species, eyes, ears etc. Flashcards
What does exopthlamic mean?
The eyeball almost fills the orbit, causes reduced eye movement
in avain/ birds
What does exopthlamic mean?
The eyeball almost fills the orbit, causes reduced eye movement
in avain/ birds
What is lacking in the avian eye?
Retractor bulbi muscles, tapetum lucidum, The retina has no vessels so birds have impaired visual acuity
What is the function of pecten and what species is it found in?
provides blood supply and it is found in birds
What is the function of scleral ossicles?
Forms the scleral ring (bones within the sclera)
found in birds but also some reptiles/fish
What is the function of scleral ossicles?
Forms the scleral ring (bones within the sclera)
found in birds but also some reptiles/fish
What is a species of bird that has a well developed olfactory bulb?
Vulture
How are avian ears different to mammalian ears?
They have no auricle/ pinna
some birds have an operculum/ accessory structure of the external ear which aids in sound location
What is the middle ear columnella, what animal is it found in?
equivalent of the stapes in mammals
What is one adaptation to the eyelids in snakes?
The eyelids are fused and cannot move, they fuse to form the spectacle
What is the spectacle in snakes?
a transparent covering for protection
can have issues with dysecdysis
Where does the vomeronasal organ in snakes receive data from?
The tongue rather than the oral cavity
What is olfaction important in (in snakes)
mating and hunting
What is the reptillian ear like?
Absence of external ear, has a middle ear columnella like birds, no coiled cochlear duct
What are the three main functions of fish eyes
collecting light, accomodation, and transforming images into neural signals
Why does a fish lens need to be more mobile?
Water has a higher refractive index
What is the retractor lentis?
a muscle that is attached to the falciform ligament that pulls the lens backwards from a relaxed position
What do fish nostrils connect to?
a nasal sac that contains nerve endings, these nerves then pass information onto the olfactory bulb and then the brain
What makes up for the reduced movement of the eyes in birds?
long neck and mobile occipitoatlantal joint, lower lid of the eye is also larger and more moveable
What do birds have to counterract the lack of movement in the eye?
More mobile atlantooccipital joint, long necks
thicker more mobile lower eyelid
What is one way you can increase the available light to the pupil?
in terms of iris/pupil
wider aperture
What is the middle ear columnella in birds the equivalent of in mammals?
It is the equivalent of the stapes in mammals
What is the main difference in the vomeronasal organ between reptiles and mammals?
reptiles receive data from the tongue rather than the oral cavity
How do fish with swim bladders detect vibrations/ movement in the water?
using lateral lines
