Chapter 15 Sensory Pathways and Somatic nervous System Review

15.1 Is afferent division sensory?

yes, sensory

15.1 Function of afferent division

Carries signal from body TO the CNS

15.1 What is the direction of Afferent Division

Input to the CNS

15.1 Sensory receptors for afferent division

Touch

Pain

Temperature

Proprioception

15.1 What is the visceral sensory info for afferent division?

From internal organs

15.1 Is efferent division sensory?

No, motor

15.1 Function of Efferent Division

Carries commands FROM the CNS to the body

15.1 What is the direction of efferent Divisions?

Output from the CNS

15.1 Components of efferent divisions?

Somatic nervous system - Voluntary control

Autonomic nervous system - involuntary control

Sympathetic - fight or flight

Parasympathetic - rest and digest

15.1 List the special senses

Olfaction

Gustation

Vision

Equilbrium

Hearing

15.2 Describe structures and proteins correlate to receptors, and give an example

each receptor has a specialized proteins or channels that are activated by a certain input

Example: Photoreceptors in eye, detect light, but not sound

15.2 Explain selective activation and how its correlates to receptors

All receptors have a threshold and will only send a signal if that correct stimulus reaches a certain strength

15.2 How does the receptor field size affect sensitivity

Smaller = more precise and sensitive

15.2 describe tactile receptors ( part of mechanoreceptors )

provide sensation of touch, pressure, sensation

15.2 describe baroreceptors ( part of mechanoreceptors)

detect changes in blood vessels in digestive, respiratory, and digestive tracts.

15.2 How does the density of receptor affect sensitivity?

More receptors in a area = greater sensitivity

example : lips have more density than the elbow

15.2 How does receptor type and adaption affect sensitivity?

Some adapt quickly(smell receptors), others adapt slowly (pain receptors)

15.3 List general senses

Touch

Pressure

Temperature

Pain

Vibration

Proprioception

15.3 Receptor for touch and its function?

Mechanoreceptors

Respond to changes ( deformation)

15.3 Receptor for pressure and its function?

Pacinian Corpuscle

When skin is pressed, layers of corpuscle gets squished

15.3 Receptor for temperature, and function

Thermoreceptors

Hot / cold

15.3 Receptor of vibration, and function?

Pancinian corpuscle

When skin is moved or shaken, layers of corpuscle vibrate

15.3 Receptor of proprioception

Muscle spindles

Muscle stretch, tension in tendons

15.4 Describe the Spinothalamic pathway, and the order it goes?

Carries pain, temperature, and crude touch

Body, spinal cord, thalamus, brain

15.4 Describe posterior column pathway, and the order it goes?

Carries fine touch, vibration, proprioception

Body, spinal cord, brainstem. thalamus, brain

15.4 Describe the spinocerebellar pathway, and the order it goes?

Carries proprioception

Body, spinal cord, cerebellum

15.5 Explain somatic motor pathways

nerve pathways that carry voluntary movement commands from your brain to your skeletal muscles

15.5 Function of somatic motor pathways

Allow voluntary muscle movement

Control reflexes

Coordinate smooth, accurate actions

Help maintain posture and balance

Describe the first order neuron, give an examplw

Carries sensory info from sensory receptor to spinal cord

Touching something hot, first order neuron sends signals from skin to spinal cord

where does the first order neuron start?

Sensory receptors (skin, muscles )

Where does the first order neuron end

Spinal cord

Describe the second order neuron, give an example

Carries signal from spinal cord to thalamus

Second order neuron takes info from spinal cord to thalamus for processing

Where does the second order neuron start?

Spinal cord

Where does the second order neuron end?

Thalamus

Describe the third order neuron, give an example

Carries signal from thalamus to specific sensory area in. cerebral cortex

Sends the processed signal to a sensory area so you can feel sensation

where does the third order neuron start?

Thalamus

Where does the third order neuron end?

Somatosensory cortex