In class activity 9.1 and 9.2

Match the different types of sensory receptors

- Mechanoreceptors: sensitive to mechanical stimuli such as deformation, stretching. or bending of cells. Provide sensations of touch, pressure, vibration, proprioception and hearing and equilibrium. Monitor stretching of blood vessels and internal organs. - Thermoreceptors: detect changes in temperature - Photoreceptors: detect light that strikes the retina of the eye. -Chemoreceptors: detect chemicals in the mouth (taste), nose (smell), and body fluids. - Nociceptors: respond to painful stimuli resulting from physical or chemical damage to tissues.

Fill the blanks The use of organizational and functional features of the nervous system to tell different stimuli apart is called (______1_______) Sensory systems encodes 4 attributes of stimulus: (__________2_________) includes each unique sensation, encoded by the sensory receptors that activated when stimulus is applied; (_______3_______) is encoded by the length of action potentials in sensory neurons; (______4______) depends on two main factors, frequency of action potentials generated in response to stimulus, and number of sensory receptors activated by stimulus; the location of the activated receptive field will encode what is called (______5______).

1. sensory encoding 2. stimulus modality 3. stimulus duration 4. stimulus intensity 5. stimulus location

Match the four events involved in the process of sensation using the figure

Box A: Sensor input is integrated in the CNS Box B: Stimulus is transduced Box C: Stimulation of sensory receptor Box D: AP are generated

Receptor vary in how quickly they adapt. Classify the statements below as being tonic or phasic. 1. Known as rapidly adapting receptors 2. Know as slowly adapting receptors 3. Continues to produce a significant response as long as the stimulus persists 4. Responds when the stimulus is first applied -the on response- and then cease to respond while the stimulus is maintained. 5. Some of these receptors also produce a second response called the off response when the stimulus is removed. 6. Specialized for signaling changes in a s stimulus 7. Associated with stimuli that require constant monitoring 8. Baroreceptor is an example of this stimulus 9. As an example of this stimulus, the brain must be continuously informed about the level of arterial blood pressure in order t maintain the driving force for movement of blood through body tissues 10. As an example of the stimulus, you normally notice your clothes touching your body when you first put them on and then are unaware of them after that.

1. phasic 2. tonic 3. tonic 4. phasic 5. phasic 6. phasic 7. tonic 8. tonic 9. tonic 10. phasic

Classify the following as fast pain or slow pain receptor. 1. Dull, aching sensation 2. Sharp, pricking sensation 3. Well localized 4. Poorly localized 5. pain felt with minor toothache 6. Sensory neurons associated with mechanical or thermal nociceptors 7. Pain felt from a needle puncture or a knife cut to the skin 8. Signals are transmitted along small A-delta fibers 9. Signals transmitted along small C fibers 10. Conduction velocities from 12-30 m/sec 11. Conduction velocities ranging from 0.5 -2 m/sec 12. Unmyelinated axons 13. Myelinated axons

1. slow 2. fast. 3. fast 4. slow 5. slow 6. fast 7. fast 8. fast 9. slow 10. fast 11. slow 12. slow 13. fast

Fill in the blank The (___blank 1___) of a neuron is the stimulated physical area, specific group of chemicals, or particular set of sound frequencies that causes a response in that neuron. The advantage of a somatic sensory neuron having overlapping receptive fields is that it improves stimulus localization because the rain is able to compare the (____blank 2____) (____Blank 3_____) are slow adoption receptors that respond to steady pressure changes. (___Blank 4____) is defined by perception of body movement. Cold and warmth are detected by (____blank 5___), free nerve endings that are present in the skin. (___Blank 6___) respond to various stimuli, including mechanical stimuli, extreme thermal stimuli, and chemicals released from damaged tissue. (___Blank 7____) are located in the upper part of the dermis of glabrous skin and are rapidly adapting receptors. (____Blank 8___) pain that it felt at a site other than the place of origin is called (___blank 9___) Most sensory pathways (___blank 10___) (cross over to the opposite side) as they course through the spinal cord or brain stem.

Blank 1: Receptive field Blank 2: Receptive area Blank 3: Merkel discs and Ruffini corpuscles Blank 4: Kinesthesia Blank 5: Thermoreceptors Blank 6: Poly-modal nociceptors Blank 7: Meissner Corpuscles Blank 8: Visceral organ Blank 9: Referred Pain Blank 10: decussate

The following questions are in reference to pain sensation. Define the two types of pain pathways (_____Blank 1____) activated by nociceptors provide unconscious protective responses when a noxious stimulus begins to damage the body. (___Blank 2___) allow pain information to be processed by higher centers. Match the different type of pain (____Blank 3___) results from stimulation of nociceptors in internal organs (___Blank 4___) arises from stimulation in skin, skeletal muscles and joints. (___Blank 5___) results from stimulation of nociceptors in internal organs felt at different sites other than the place of origin.

Blank 1: Spinal Reflexes Pathways Blank 2: Ascending Pathways Blank 3: Visceral pain Blank 4: Somatic pain Blank 5: Referred pain

Sensory receptor morphology

Box 1: Encapsulated nerve endings Box 2: Free nerve endings (dendrites) Box 3: Separate cell Example of free nerve endings: pain, thermal, itch, tickle and some touch sensation Example of separate cells: Special senses (eye retina, hair cells, for hearing and equilibrium) Example of encapsulated nerve endings: pressure, vibration, and some touch sensation Which type of sensory is more sensible/specific? Why? : Encapsulated -due the presence of connective tissue capsule.

Identify the sensory pathways and different nervous system structures Fill the blanks: The (____blank 1_____) conveys action potentials for touch, pressure, vibration and proprioception to the cerebral cortex. The (____blank 2___) conveys action potential for pain, temperature, itch, and tickle to the cerebral cortex. In the anterolateral spinothalamic pathway the axons of the (____blank 3___) -order neurons decussate in the spinal cord, so affects will be felt on the opposite side of the stimulus.

Box 1: third order neurons Box 2: second order neurons Box 3 : first order neurons Box A: Cerebral Cortex Box B: Thalamus Box C: Brain Stem Nuclei Box D: Brain Stem Box E: Sensory receptors Box F: Spinal Nerves Box G: Spinal Cord Blank 1: dorsal column pathway Blank 2: anterolateral spinothalamic pathway Blank 3: second

Label the structures located in the muscle fiber

Box a: tendon Box b: sensory axon Box c: muscle spindle capsule Box d: alpha motor neuron to extrafusal muscle fibers Box e: gamma motor neuron to intramural muscle fibers Box f: extrafusal muscle fibers Box g: tendon organ capsule Box h: muscle spinal capsule