Transcript The Senses - MsTrettensClasses

 Reflex: quick,
automatic
response to a
stimulus
 Allows your body
to respond to
danger
immediately
 Reflex Arc:
includes a
sensory receptor,
sensory neuron,
motor neuron,
and effector
 Which portion of the PNS is responsible for the
fight or flight response?
 What are some ways that your body responds?
 What is the evolutionary history to this
response? (why did it arise in the first place?)
 Fight or Flight Video
 Sensory Receptors: neurons that react to a specific
stimulus
 5 types of sensory receptors:
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Pain receptors
Thermoreceptors
Mechanoreceptors
Chemoreceptors
Photoreceptors
 Sensory Receptors are located throughout the body
but they are concentrated in the sensory organs
(eyes, inner ears, the nose, the mouth, and the skin)
 Pain receptors:
 Located throughout the body, except in the
brain
 Respond to chemical released by damaged cells
 Thermoreceptors:
 Located in the skin, body core, and
hypothalamus
 Detect variations in temperature
 Mechanoreceptors:
 Located in the skin, muscles, and inner ears
 Respond to touch, pressure, stretching of muscles,
sound, and motion
 Chemoreceptors:
 Located in the nose and taste buds
 Sensitive to chemicals in the external environment
 Photoreceptors:
 Located in the eyes
 Sensitive to light
 Iris: Color portion of the eye
 Pupil: middle of the iris, allows light to enter
eye
 Lens: Focuses light onto the back of the eye
(Retina)
 Photoreceptors are arranged in a layer onto
the retina
 Rods: Black and white
 Cones: Respond to different colors
 Cones are concentrated on the macula fovea
 Nearsightedness:
 Close objects are
clear
 Distant objects
are blurry
 Eye is too long
 Farsightedness
 Distant objects clear
 Near objects blurry
 Eye is too short
 Area on the retina
without receptors that
respond to light
 Located where the optic
nerve exits the eye
 How we see
Copy the highlighted charts into your Notebook
and record your data at each of the stations.
For each station, copy the highlighted chart
into your Notebook and follow the provided
directions.
 Station 1: Where is your blind spot?
 Station 2: Optical Illusions: What is real?
 Station 3: How is your depth perception?
 Station 4: Reaction Time
 The ear has two sensory functions: hearing and
detecting potential changes associated with
movement
 How we hear
 Smell chemoreceptors in the lining of the nasal
passageway respond to specific chemicals and
send impulses to the brain through sensory
nerves
 Much of your taste of food is actually smell
 Taste: chemical sense. Taste buds detect taste
 5 tastes:
 Salty, Bitter, Sweet, and Sour, Umami (meaty)
 How we smell and taste
 All regions of the skin are sensitive to touch
 The skin is actually the largest sense organ
 Skin contains sensory receptors that respond
to temperature, touch (pressure), and pain
 Not all parts of the skin are equally sensitive to
touch because not all parts have the same
number receptors
 Greatest density of touch receptors are found on
fingers, toes, and face
 How are skin perceives touch
 Station 1: A penny heard…
 Station 2: Are you a super taster?
 Station 3: The Link Between Taste and Smell
 Station 4: Two Point Touch