lect 7 - chemorecpetion Flashcards
(17 cards)
3 main chemosensory systems
- olfaction (nose smelling)
- gestation (taste)
- vomeronasal
vomeronasal system (VNS)
aka Jacobson’s organ
- accessory olfactory system, especially in squamates
role of forked tongue
delivers particles to the vomeronasal organ, allowing directional chemical sensing
chemosensory adaptations in caecilians
tentacles between eye and nostril, connected to the vomeronasal organ
pheromone producing glands in amphibians + reptiles
cloacal, mental, femoral, skin (mucus/granular)
lizards with most developed chemical glands
sit-&-wait predators
eg. iguanas and cordylids
faeces signaling
in Iberolacerta cyreni lizards
faeces contain sex-specific chemical compounds influencing mate selection
anal glands in snakes
release sex pheromones, especially in females to attract males
usefulness of chemorecption
- long term signal
- works in dark/underground/underwater
epithelium of the nasal cavity
where various genes that are associated with how many kinds of different molecules that can detect are unregulated + expressed
taste receptors
T1R = sweet/umami receptors
T2R = bitter receptors
tongue movements
- simple downward extension
- single oscillation
- multiple oscillations
granular vs mucus glands
granular (poison gland)
- concentrated around head
- signal pain towards other animals
mucus
- throughout the skin (high density)
- used to keep skin moist
lizard chemical-producing glands
follicular gland
- hole in the skin with a waxy plug to rub across surface
pre-anal glands
- leave reflective UV trail
femoral pores
- sexual selection
chemical signaling in turtles
- mental glands
- cloacal
- musk/rathke’s gland (foul liquid for courtship)
apical pits
integumentary sensory organs detect changes in pH
- in crocs
paracloacal glands
in crocs, involved in individual recognition and sex identification
