3/9/15

When you have a sinus infection or some other cold that decreases your ability to smell have you also lost your sense of taste? Why do you

think that is? If you’re not sure speculate on the connection between the two.

CHEMICAL, SKIN, AND BODY SENSES

• Smell – allows a person to taste– If your sense of smell were not working, an onion

and an apple would taste very much alike to you

1. Odors are detected by receptor neurons high in each nostril

2. The receptors send information about the odors to the brain via the olfactory nerve

One odor can also be masked by another which is how air fresheners work.

Taste

• Taste – sweetness, sourness, saltiness, bitterness, and umami (meaty or savory)– The flavor of a food is more complex than

taste alone.– Flavor depends on odor, texture, and

temperature as well as taste

• Example: apples and onions taste similar but their flavors differ greatly

– Taste is sensed through receptor neurons located on taste buds on the tongue.

– Sensitivities to different tastes can be inherited

– Taste cells reproduce rapidly enough to completely renew themselves in a week.

– The taste system is one of the most resilient of all the body’s sensory systems

Video

• http://youtu.be/A_aevsFwlJA

Touch• Touch is a combination of pressure, temperature, and pain

– Example: Premature infants grow more quickly and stay healthier if they are touched

• Sensory receptors located around the roots of hair cells fire where the kin is touched.

• Different parts of the body are more sensitive to pressure

Temperature

• What is your normal body temp?• 98.6°F• The receptors for temperature are neurons just

beneath the skin

• Example: When you first jump into a swimming pool, the water may seem cold. Yet, after a few moments the water feels warmer as your body adjusts to it.

Pain

• Pain originates at the point of contact

1. Pain message to the spinal cord 2. Then to the thalamus in the brain 3. Then to the cerebral cortex where the person

registers the location and severity of the pain.

Trivia

• Where do you think the 2 most sensitive parts of your body are? (The most receptors in a location).

• Back of knee• Neck

Body Senses• Try this activity• Stand up and close your eyes• Do you have to look in a mirror to be certain that

you are still upright? No• Vestibular sense tells you whether you are

physically upright without having to use your eyes.

• Sensory organs in you ears monitor your body’s motion and position in relation to gravity.

• It also tells you whether your body is changing speeds, such as in an accelerating automobile.

Kinesthetic

• Try this activity• Close your eyes then touch your nose with your

index fingers (right then left)• How did you locate your nose with your eyes

closed?• Kinesthesis is the sense that informs people about

the position and motion of their bodies.• Sensory information is fed to the brain from

sensory organs in the joints, tendons, and muscles.

Activity

• In groups of 2