CH 13 Study guide

Sensory Receptors Classified by Stimulus Type

• Photoreceptors

• Mechanoreceptors

• Chemoreceptors

• Thermoreceptors

Sensory Receptors Classified by Location

• Exteroreceptors

• Proprioceptors

• Interceptors

Photoreceptors

Stimulus: Light

Location: Retina of eye

Mechanoreceptors

Stimulus: mechanical pressure or distortion

Location: Skin, Muscle, inner ear

Chemoreceptors

Stimulus: Chemical changes

Location: Taste buds, olfactory epithelium in the nose

Thermoreceptors

Stimulus: Temperature changes

Location: Skin, Hypothalamus

Exteroreceptors

Location: Near body surface

Function: Respond to external stimuli (touch, pressure, temp)

Proprioceptors

Location: Muscle, Tendons, Joints

Function: Provide the body info abt position and movement

Interceptors

Location: Internal Organs

Function: Monitor internal conditions (BP, pH levels)

Steps in regeneration of PNS Axon

1) Injury

2) Wallerian Degeneration

3) Clean up by macrophages

4) Schwann Cells activate release growth factors

5) Axon growth

6) Guidance by schwann cells

7) Axon reconnects

8) Recovery

Cerebral Cortex

Location: Cerebrum Outer layer

Cranial Nerves: I (Olfactory) and II (Optic)
Function: Sensory Perception of smell (I), Vision (III)

Brainstem- Midbrain and Pons

Location: Proximal of brainstem

Cranial Nerves: III (Oculamotor), IV (Trochleaar), V (Trigeminal)

Function: Eye movement (All three), Facial Sensation (III), and Chewing (V)

Brainstem- Medulla

Location: Lower part of Brainstem

Nerves: VI, VII, VIII, IX,, X, XI, XII

Function: Eye movement, facial movement and taste, hearing and balance, swallowing and taste, autonomic function, head movement, tounge movement

Nerves Plexus- Benefits of the body

• Efficient communication

• Redundancy and reliability

• Flexibility in responses

• Simplified wiring

• Segmented control

Brachial Plexus

• C5 to T1

• Controls motor and sensory function of the upper limb

Cervical Nerves

• C1-C8

Thoracic Nerves

• T1-T12

Lumbar Nerves

• L1-L5

Sacral Nerves

• S1-S5

Coccygeal Nerves

• C01

Different events that could happen, resulting to damage to major nerve

• Surgery

• Trauma

• Tumors

• Spinal Stenosis

• Herniated Disc

• Compression

Inborn (Intrinsic) Reflex

Automatic Reflex

Learned (Acquired) Reflex

Acquired through experience or training

Components of spinal reflex

• 1. Receptor- sensory neuron detects stimulus

• 2. Sensory Neuron- carry impulse to spinal cord

• 3. Integration Center- interneuron process signal in spinal cord

• 4. Motor Neuron- Carries impulse away from spinal cord

• 5. Effector- Muscle or gland responds to impulse

When the reflexes below are activated what is the end motor effect on involved muscle

Tendon reflex

• Inhibits contracting muscle

When the reflexes below are activated what is the end motor effect on involved muscle

Flexor Reflex

• Flexor muscles contract, extensor muscles relax

When the reflexes below are activated what is the end motor effect on involved muscle

Crossed-extensor reflex

• Contralateral extensor muscles contract

When the reflexes below are activated what is the end motor effect on involved muscle

Plantar Reflex

• Toe flexion