Mod3-Obj6: Sensory receptors and the types of stimuli they detect

Question 1

For the nervous system to detect, interpret and respond to environmental stimuli…

Answer 1

1. ) Sensory receptors must detect a stimulus
2. ) Neural pathways carry
   - Sensory signals to the CNS (sensory neuron)
   - Through the CNS (interneurons)
   - Motor signals from the CNS to an effector (motor neuron)
3. ) An effector muscle or gland brings about a response

Question 2

Sensory receptors

Answer 2

-Specialised to detect a stimulus and convert the stimulus information into an electrical signal

Question 3

Sensory receptors are classified according to three overlapping criteria…

Answer 3

1. ) Structural complexity
2. ) Type of activating stimulus
3. ) Location

Question 4

Sensory receptors are classified by structure

Answer 4

1. ) Simple receptors

2. ) Complex receptors

Question 5

Simple receptors

Answer 5

The dendrites of sensory neurons

Question 6

Complex receptors

Answer 6

Distinct cells connected to sensory neurons

Question 7

Simple sensory receptors

Answer 7

Detect stimuli associated with our general senses

• Temperature
• Pain
• Touch
• Pressure
• Proprioception

Question 8

Complex sensory receptors

Answer 8

Detect stimuli associated with our special senses

• Vision
• Smell
• Taste
• Hearing

Question 9

Classification by stimulus

Answer 9

5 basic types

1. ) Thermoreceptors
2. ) Photoreceptors
3. ) Nociceptors
4. ) Mechanoreceptors
5. ) Chemoreceptors

Question 10

Classification by stimulus: Thermoreceptors

Answer 10

Temperature receptors

-Respond to internal and external temperature changes

Question 11

Classification by stimulus: Photoreceptors

Answer 11

Are visual receptors

-Respond to light the strikes the retina of the eye

Question 12

Classification by stimulus: Nociceptors

Answer 12

Pain receptors

-Respond to damaging stimuli e.g.) heat, abrasion, pressure

Question 13

Classification by stimulus: Mechanoreceptors

Answer 13

Respond to mechanical stimuli that distort cells (e.g. bend, stretch & twist)

• Tactile receptors: Provide sensations of touch, pressure and vibration
• Baroreceptors (aorta & carotid arteries): detect blood pressure changes
• Hearing receptors

Question 14

Classification by stimulus: Chemoreceptors

Answer 14

Respond to water-soluble or lipid-soluble chemicals

• Provide us with sensations of taste (mouth) and smell (nose)
• Monitor the pH, ions (e.g. H+ or Na+), CO2 and O2 and levels of body fluids

Question 15

Classification by location

Answer 15

1. ) Exteroceptors
2. ) Interoceptors
3. ) Proprioceptors

Question 16

Exteroceptors

Answer 16

Respond to stimuli arising outside the body

-Found in sense organs and the skin

Question 17

Interoceptors

Answer 17

respond to stimuli arising within the body

-Produce feelings of stretch, pressure, pain, hunger and nausea

Question 18

Proprioceptors

Answer 18

Restricted to skeletal muscles, tendons, joints and ligaments
-Provide information about our body position and movements