Overview of the Main Sensory Organs

Question 1

What are the 5 different types of sensory receptors?

Answer 1

Thermoreceptors
pain receptors
mechanoreceptors
chemoreceptors
electromagnetic receptors

Question 2

What does taste involve?

Answer 2

ions bound in the membrane of taste chemosensory axons

VG ion channels that produce depolarising potentials when taste chemoreceptor cells interact with tasetants

Question 3

The stages of smell?

Answer 3

1) odour molecules bind to receptors in olfactory membrane
2) olfactory receptors send signals to olfactory bulb
3) signals relayed via converged axons
4) the signals are transmitted to higher regions of the brain

Question 4

What are rods and cones?

Answer 4

rod cells - extremely sensitive, triggered by single photon, used in low light levels
Cone cells - see colour but require brighter light

Question 5

What happens in a dark response?

Answer 5

rhodopsin inactive
Na+ channels open
rod depolarised
glutamate released which effects bipolar cell

Question 6

What happens in a light response?

Answer 6

rhodopsin active
Na+ channels closed
rod hyperpolarised
no glutamate released

Question 7

How we hear?

Answer 7

outer hairs amplify sound vibrations
inner hairs detect these vibrations and excite nerve fibres of the cochlea or auditory nerve
inner ear hosts vestibular mechanoreceptors that excite the vestibular neurons of the auditory nerve