chapter 17-23 Flashcards
Rectilinear motion
large-bodied snakes
Slow movement
belly scales are alternately lifted
Lateral undulation
common locomotion
Concertina Locomotion
- involves alternately pulling
crawling through tunnels
Sidewinding
snakes crawling on smooth
or slippery surfaces
Snakes - Chemosensory
pit-like Jacobson’s organs
(vomeronasal organ) in the roof of the
mouth, which are olfactory organs.
Snakes - Thermosensor species
(pit vipers such as
rattlesnakes) have heat-sensitive pit
Predation Snakes
grabbing it and swallowing
kill their prey by constriction
venom
Colubrid snakes
have Duvernoy’s gland = homologous to
venom gland of vipers/elapids
Neurotoxic
nervous system or muscle function
Cytotoxic
breaks down and digests tissue
Hemotoxi
causing blood to congeal, or lowering blood pressure, immobolized
Aglyphous
no fangs
Opisthoglyphus
rear fangs
Solenoglyphus
= large hollow fangs, rotate forward
Proteroglyphus
fixed, hollow fangs on front of maxilla
Shell and Skeleton turtles
Ribs and vertebrae are fused to the shell and the head and
limbs can be
Plastron formed mostly from
dermal ossification
Entoplastron from interclavicle
* Epiplastra from clavicles
prototherians, crocodilians, and birds.
furcula
Birds - retain the clavicle and the
interclavicle joins to the two clavicles
One hinge:
box turtles the anterior and
posterior ends of the plastron can be
raised to close off the front and rear
openings of the shell.
Two hinges:
mud turtles there are two hinges,
plastron is often reduced, so “closing”
isn’t as complete
Cryptodira
Hidden-necked turtle
Suborder PPleurodira –
Side-necked turtles
Tubercle
protuberances of skin
Barbels:
whisker-like protuberances
usually on chin
Keel:
ridge along midline of carapace
Serrations:
jagged edge usu along shell or
beak
Vent
same thing as cloaca
makes normal
breathing impossible
Fusion of ribs to shells
Lungs are attached to carapace
dorsally and
laterally; to viscera ventrally via connective
tissue
Turtles: respiration
Downward movement of viscera pulls lungs
down, expanding space, allows inhalation
Softshell turtle respiration
leathery skin
septum - turtle
that partially divides the ventricle into separate left
and right chambers.
Temperature-Dependent Sex
Determination
Higher incubation temperatures
produce the larger sex, which in
turtles is female