Experimental Design: Studying People Scientifically

Activity 6A: Finding the Nerve

September 17, 2014

Activity 6A: Finding the NerveSeptember 17, 2014

Getting Started: What are our five senses? What is the location of the nerves that sense our environment for each of the five senses?

Introduction: Read the top of pg A-25. That’s it!!

Finding the Nerve

You probably found that some parts of your

arm were more sensitive than others. In this reading you will learn about some of the reasons for these differences.

Why do different parts of your body have different sensitivities to touch?

6A

Challenge: Rewrite the challenge question in your own words.

Key Words: neuron, nerves, nervous system

Procedure: This activity is supported by a directed activities related to text strategy called Stopping to Think.

Results: Stopping to Think 1

Stopping to Think 2Stopping to Think 3Stopping to Think 4

Analysis: Answer Analysis Questions 1 through 4.

Reflection:

Stopping to Think

• Helps you think about what you are reading and, in some cases, to apply what you have read.

• The questions focus your attention on to important ideas of what you have just read.

These could be test questions*

Stopping to Think 1

a. Why are the nerves that take information from our world called sensory neurons?

• Nerves that gather information from the world around us are called sensory neurons because they are associated with the senses, such as sight or touch.

a. What kind of information do sensory neurons detect?

• Sensory neurons can detect information from all of our five senses: taste, touch, smell, hearing and sight.

Stopping to Think 2

a. Someone accidentally bumps into you in the hallway. What part of your body detected the feeling of being bumped?– Whatever part of your body that got bumped is where it would be

detected.

b. Where in the body is this feeling analyzed?– The feeling is analyzed in your brain.

c. “Inter” means between. Why are the neurons in the spinal cord and brain called interneurons?– Interneurons connect the sensory and motor neurons. This me4ans

they go between the sensory neurons and motor neurons in the spinal cord, or they go between the sensory neurons and the motor neurons in the brain where the messages are analyzed.

Stopping to Think 3

a. Is breathing completely involuntary? Explain (involuntary = done without thinking about)

• No, I can make myself breathe faster or slower, but I don’t have to think breathing to breathe. For example, I still breathe when I am asleep.

a. Explain how motor neurons can be part of both the voluntary and the involuntary nervous systems.

• Sometimes they’re voluntary like when I pick up a pencil and sometimes they’re involuntary like when food gets moved through my digestive system.

Stopping to Think 4

a. When you decide what to wear in the morning, which of the three parts of your brain do you use? Explain

• I use my cerebrum, because that is the part of the brain responsible for thinking and reasoning.

a. What is a benefit of the cerebrum having folds and wrinkles?

• This makes more room for neurons than if the cerebrum was smooth.

a. What part of the brain enables you to breathe, even when you are asleep?

• The brain stem. It controls all basic life functions, such as breathing, heart rate, and blood pressure.

Analysis 1

a. Where would you expect to have more touch receptors: on the palm of your hand or on the back of your hand? Explain your reasoning?

b. Explain how you could test your answer to question 1a.

Analysis 2

• When your partner touched you with the toothpick points in Activity 5, how did you sense it? Describe or draw the path through the nervous system that enabled you to identify if it was a one – or two – point touch.

Analysis 3

Review your results from Activity 5, “Can You Feel the Difference?” Based on what you now know, where on your arm – fingers, palm, or forearm – do you have the fewest touch receptors?

Analysis 4

• Describe the structures that make up the nervous system.

Nervous System

Sensory Neurons- sense the world

around us

Motor Neurons- tell our muscles

to move

Interneurons -connect sensory

neurons to motor neurons

and to brain cells.

Brain

Cerebrum- allows usto think and make

Decisions.

Cerebellum- Allows us to movewith coordination.

Brain Stem- isResponsible for

basic life processes

such as heart rate and breathing.

• The nervous system helps us sense the world around us, and tells our muscles to move. Neurons connect to the spinal cord and the brain. The brain is responsible for interpreting everything the nervous system senses and then it tells our body how to react.

• Why do different parts of your body have different sensitivities to touch?