Mechano/Chemo Reception Flashcards
What is a trichoid sensilla?
Simple mechanoreceptors - they are phasic receptors so they stimulate only during bending
What is a campaniform sensilla?
Dome-like mechanical stress receptor - respond to mechanical stress of integument such as coordination of legs and information on posture - NERVE RESPONSE IS TONIC (CONTINUOUS ACTIVITY)
What is a chordotonal sensilla?
Tension receptor - subcutaneous, each organ has a scolopidium which has 3 parts: neuron, scolopale cell enveloping neuron and attachment cell. Can be highly evolved auditory organs.
What are the 2 parts of a mechanoreceptor?
Specialised cuticular structure and nerve ending in contact with it
In mechanoreceptors, what produces the hair and what produces the socket?
Trichogen cell = hair
Tormogen cell = socket
What is the Johnston’s organ?
Specialised chordotonal organ which detects movements of the antennal flagellum - lies in 2nd segment of antennae (is a flight speed indicator which orientates insects with respect to gravity)
What detects taste?
Contact receptors
What detects smell?
Olfactory sensilla
What are olfactory binding proteins?
Water soluble proteins that carry odour molecules through the mucus until they reach the olfactory receptors
What are olfactory receptors?
Proteins in cell membranes that detect odourants
What are mushroom bodies?
dense networks of neurons composed of Kenyon cells that are essential for olfactory learning and memory
What is the lateral horn?
Multiple types of neurons which integrate information from different sources and are responsible for innate behavioural responses
What is the one receptor-one neuron rule?
Insects have one neuron that expresses few types of receptors but it has a narrow receptive range (one receptor per odour) so a limited number of odours are perceived with high sensitivity
What is a seta?
Chintious projection with which the tip of the nerve ending is in contact with
What is tonic vs. phasic reception?
Phasic is stimulated only when being bent or straightened (response to change in stimulus). Tonic is stimulated all the time.
