Vertebrate Sensory Systems

Question 0

Describe the elements in the spinal chord

Answer 0

Gray matter (nuclei, route sensory stimuli to the brain or effectors (muscles) via interneurons)
White matter (axons)
Spinal nerves (segmental roots or ganglia with cell bodies)
- controls the many motor functions

Question 1

Describe the nervous system

Answer 1

Somatic and visceral sensory nerves move through the afferent pathways to the brain and spinal chord.
The brain releases signals that move through the efferent (motor) pathways.
They can either go to the somatic motor nerves (voluntary) or the visceral motor nerves- automatic/involuntary
The result is either sympathetic: thoracic and lumbar spinal chord outflow (speeds up) or parasympathetic: craniosacral outflow (slows down

Question 2

Describe the two types of spinal nerves

Answer 2

Dorsal root (afferent neurons- visceral and somatic sensory neurons)
Ventral root (efferent neurons- autonomic and somatic motor fibres)

Question 3

Describe the vertebrate inner ear

Answer 3

Has ampullae with cristae which note angular velocit/dynamic equilibrium.
As head moves, inertia causes a slight relative movement of fluid in at least one semicircular canal. Also senses acceleration.

Question 4

Decscribe hearing adaptations for land

Answer 4

Major source of sound is airborne and these waves have a large amplitude but small force so are easily deflected when encountering a denser medium.

Question 5

Explain the mammalian middle ear

Answer 5

Converts airborne sound into vibrations in fluid in membranous labyrinth.
Tympanum collects sound energy. Auditory ossicles amplify and transmit sound energy to inner ear via oval window. This then makes waves have a small amplitude but large force vibrations in fluid.
Has three bones- columella, incus and malleus.

Question 6

Go over all the chemo reception crap and photo reception

Answer 6

Or else you’re fucked.