Science 6

Optional Unit: Human Body Control Systems

Unit overview

The structure and function of the central nervous system and the endocrine system are examined in this unit. These topics do not lend themselves to a lot of investigations involving student experimentation. The focus of the unit will involve predominantly research of print and audiovisual information about the human nervous and endocrine systems.

Science writing and reading activities, as discussed in this Guide, are essential in this unit. Readings from reference books, journals, magazines, and newspapers will be the primary information gathering method employed. In order for students to assimilate this material and convey the results of their research to their classmates, writing is essential. Writing in personal, reflective journals and creating innovative reports in various formats are strategies through which students may refine their understanding of the concepts in this unit.

Examples of activities which contain writing or reading components are found in the Suggested activities section of this unit.

Science challenge, as described in this Guide, is meant to extend students' critical and creative thinking abilities in the context of the science concepts being studied. Activities involving science challenge should be incorporated into science lessons in each unit. The challenge is intended to give each student a chance to investigate an area of interest in more depth than would be possible for all students in a class to do. Science challenge is a key strategy for bringing the Adaptive Dimension to the classroom, and for encouraging independent learning. The extension phase of each lesson is an ideal place for students to create their own challenge opportunities or to choose from opportunities suggested to them.

Factors of scientific literacy that should be emphasized

Concept development

grade 1
- identification of the senses
grade 4
- function of the brain in interpreting sensory information
grade 10
- human body systems
grade 12 Biology
- animal systems

Foundational and learning objectives for Science and the Common Essential Learnings

Recognize the importance of the central nervous system.
1. Describe the function of the central nervous system.
2. Describe the function of the peripheral nervous system.
3. Compare voluntary and involuntary actions.
4. Evaluate the importance of reflex actions.
5. Describe the structure and function of different types of nerve cells.
6. Locate major regions of the brain.
7. Describe the known functions of different regions of the brain.
8. Identify several disorders of the nervous system.
Recognize the importance of the endocrine system.
1. Explain the function of the endocrine system.
2. Identify some of the endocrine glands.
3. Describe the function of some endocrine glands.
4. Associate the major hormones with the glands that produce them.
5. Describe the functions of each of the major hormones.
6. Identify several disorders of the endocrine system.
Understand how knowledge is created, evaluated, refined and changed within science. (CCT)
1. Focus attention on knowledge possessed and knowledge desired with respect to the brain.
2. Gather and interpret evidence about CNS and endocrine system functions.
3. Consider how nonintrusive investigations can reveal information about the brain and nervous system.

Suggested activities

Listed below are a number of effects. Classify each according to whether the effect is a result of activity in the nervous system, the endocrine system, a combination of the two, or neither system.
- You feel a bee sting you.
- Your bee sting swells up.
- Starch in foods starts to be digested in the mouth.
- When you eat a slush drink, your head aches.
- When you're really frightened, you sometimes have a lot more strength than normal.
- Insulin controls the level of sugar in your blood.
- When you've been up 24 hours in a row, you feel tired.
- A lot of men become bald as they grow older.
- When an object is moving towards your eye, the eye automatically closes.
- Most humans grow to between 150 cm and 185 cm tall.
- You can remember when your birthday is.
- Once you learn how to ride a bike, you never have to learn again.
- Light coloured skin tends to become burned or darker when exposed to sunlight.
During your research to find the causes of these effects, each group of students should make some more statements for other members of the class to evaluate. Each statement should be submitted to the teacher for checking.
Factors: A3, B2, B16, F3
Objectives: 1.1, 1.2, 2.1, 2.3, 3.1, 3.2
Assessment Techniques: anecdotal records, homework, short answer test items
Instructional Method: research projects
Brainstorm with the class to find out what they know about the brain. Record their ideas and information in one column of a chart on the board. In a second parallel column, record questions which arise from the statements in the first column or other questions which they might generate about the brain and its functioning.

Once questions have been recorded in the second column decide how they will be distributed among the groups in the classroom. Groups might volunteer to answer one or two of particular interest to them, or the questions written on slips of paper and drawn from a hat. Ask the groups to prepare a short oral presentation to the class to discuss the results of their research. The presentation should be supplemented with posters, diagrams or other visual aids to help their classmates understand what they have found out.

Factors: B16, C2, C4, E4, F3, G2
Objectives: 1.6, 1.7, 3.1
Assessment Techniques: group evaluation, observation checklist, presentations
Instructional Methods: reports, reading for meaning
Which central line segment in the two diagrams below appears to be longer?

Which vertical line appears to be longer?
Find other line illusions and produce posters that illustrate them. Why do these effects fool our eyes?

Factors: B5, F5, G1
Objectives: 1.1, 3.2
Assessment Techniques: performance assessment, written assignments
Instructional Methods: inquiry, problem solving
A Russian scientist named Pavlov trained dogs to salivate when he rang a bell. How might this have been done? Outline a training scheme which would produce this effect. Then find out what Pavlov did.

A science fair project from several years ago involved fish which had been trained to come to the side of the aquarium when the student tapped the wall of the aquarium. How might this have been accomplished?

This process is called conditioning. How does it relate to the process of house-training dogs or teaching dogs to roll over and play dead? Do you suppose that a grasshopper could be conditioned to do something? How about an earthworm?
Hold a metre stick vertically so that its lower end is about one metre from the floor. Ask your partner to put a thumb and forefinger on either side of the metre stick, at the end closest the floor. Drop the metre stick and ask your partner to catch the metre stick between the two fingers.

Read the distance the metre stick has dropped before being caught. You will have to decide how to determine the end-point for the measurement. Will it be from the end of the stick to the top of the fingers, the bottom of the fingers or somewhere in between? Record the result. Repeat the process, recording the distance the stick has fallen each trial. Is there a learning effect involved in this procedure? If your partner doesn't catch the stick during one trial, how would this be recorded in the data? Does your partner's catching distance keep getting shorter and shorter?

Bend a 2 cm by 4 cm piece of paper into the shape of an L. Tape the strip of paper to the 50 cm mark of the meter stick so that the longer arm of the L sticks out perpendicular to the surface of the metre stick. Tell your partner to again hold the index finger and thumb at the bottom of the stick, close her eyes and catch the stick as soon as the paper hits one finger or the other. Collect data for a number of trials with this method, measuring the distance from the piece of paper to where the stick is caught. How would you report a trial when your partner caught the stick before the paper hit the finger? Occasionally move the paper strip to other places along the metre stick to alter the time between when the stick is dropped and the paper tab hits the fingers.
Analyze the data collected from your partner's catches. What trends are evident? How can this data be reported as a line graph? as a bar graph? Repeat the procedure with your partner and yourself switching roles. Compare your results with those from one other group. Are the results comparable or different? Pool all data from the class and analyze the trends in the class.
Draw an outline of your body on the central part of a piece of poster paper. On this outline, sketch the location and shape of the endocrine glands. Around the outside of the paper, briefly describe what hormone(s) each gland secretes, and the effect of each hormone.
The word endocrine is a compound word made from two Greek words. Find out what the Greek words are, what they mean in English, and how this compound word describes the endocrine glands or system.
Your brain is encased in thick bones which make up the skull. These bones are very strong and protect the brain. However, if you fall and hit your head on the floor, ground, ice, or other hard surface your brain may be injured without your skull being broken. How does the brain become injured if the skull doesn't break? How does wearing a helmet when you skate or ride a bicycle protect your brain in case of a fall? What are characteristics of a good helmet?
Taste buds to sense sweetness, sourness, bitterness, and saltiness are found in different locations on the tongue. Use a sugar solution, lemon juice, 0.1% quinine sulfate solution, and salt solution to locate areas of the tongue sensitive to each of these stimuli. (A solution of instant decaffeinated coffee could be substituted for the quinine sulfate.) Adjust the initial strength of the solution so that the effect is noticeable but not overpowering when a few mL are rinsed in the mouth.

Draw a full size outline of each tongue to be tested and determine a testing grid. Mark that grid by number on the outline of the tongue so that for each numbered location the result of the sweet, salty, bitter, and sour tests may be recorded and eventually mapped back to an outline of a tongue to show the tasting zones.

Administer the solutions to the tongue with a dropper, placing a small drop at each sampling location as determined by the chart. 15 to 30 sampling locations should be identified. Record the effect as each drop is added. As sensitive areas are located, their extent may be mapped by more intensive measuring of those locations. An alternative to administering the solutions with a dropper is to use a Q-tipş type cotton swab.

Compare the results of the testing. Does everyone have approximately similar areas of sensitivity to each stimulus, or is an area that is sensitive to saltiness in one person sensitive to sweetness in another?
Devise and conduct a test to determine a person's ability to hear. Identify as many variables as possible that may be important in conducting the test.
Some people have difficulty distinguishing between red and green. Find out what kind of tests are used to help identify this condition. Do you know someone with this condition? What effect would this have on everyday activities?
Devise a test to gauge a person's sense of touch. Do all people have equally sensitive senses of touch? Is the palm of the hand more sensitive than the back of the hand? Is the upper arm more sensitive than the fingertips?
Design an investigation to study the relationship between the sense of smell and taste. Does an orange taste sweet if you are smelling a lemon while you eat the orange? How does water taste if you are smelling an onion when you drink the water? If you plug your nose and then eat a piece of lemon, does its taste change?
Experiment with your sense of balance to see how much depends on visual cues. Can you stand balanced on one leg as easily when your eyes are shut or you are blindfolded as when you can see? Devise some other balance tests.

Be careful when experimenting with balance so that you don't fall and hurt yourself. It might be a good idea to have one or two friends ready to support you if you lose your balance.