Senses Teacher Guide

Unit

Senses

Subject

Life Science

Grade Level

ES 3-4

Activity Name(s)

Insect Sensors

Measuring Different Colors With Light

Sensing Temperature

Being Prepared

Depending on equipment you have available you may want to put students into groups of 3-4. If you want the students to work in smaller groups, allowing more interaction with the materials having this set up so that several groups of 2 do an activity while other students work on other activities like investigating different animals and their senses.

For the "Insect Sensors" activity make sure that you have tried out the digital scope and know how they will work with the activity. Digital microscopes with work differently depending on the computer platform (Mac vs PC) and the microscopes themselves.

Collecting insects needs to be planned for. You should avoid the intentional collection and killing of insects and think about places where they may die naturally. Depending on where you live there may be sources such as bee keepers who might have dead bees they can provide for you.

Getting Started

Insect Sensors

You will need access to digital microscopes. Make sure that microscopes will work with the computes that you will be using. A source for dead insects to look at is necessary. Additional equipment to collect includes tweezers or toothpicks, small clear plastic containers for the dean insects (plastic petri dishes work well), and some way to label the containers.

Measuring Different Colors With Light

You will need a light sensor and any adapter need to connect to the computer. If your sensor range can be changed make sure you test in your classroom to see what setting will work best. Additional materials include a ruler, pencil, tape, white paper or index cards, sheets of colored paper (at least 3), black or dark colored markers, and tissues.

Sensing Temperature

You will need a temperature sensor and adapter if need to connect to your computers. You may need to show students how to change the scale on their graphs in order to be able to see differences in temperature of objects. In addition cups, a source of water at different temperatures, and paper to make fans will be needed.

You should remind students of basic safety issues such as not putting anything in our mouth, no food or drink around the computers

Suggested Timeline

Each activity should take about 90 minutes or 2-45 minute periods. If you are doing the activities as centers this may spread the number of days need for all students to have an opportunity to complete the activities.

Thinking about the Discovery Questions

The "Senses" unit looks at similarities and differences in how organism perceive the world around them. The activities look at the external receptors used to see the world (eyes) and sense changes in temperature (skin).

In the first activity, "Insect Sensors" the discovery question "How does an insect find out about its environment?" gives students the opportunity to take a close look at insect eyes. They will use a digital microscope to capture images of the eye and think how the eye structure and other sensor organs help insects survive.

In the second activity, "Measuring Different Colors With Light" uses the discovery question "How do animals' senses help them survive?" to give students the opportunity to look at how light and color might influence how animals see the world around them.

Finally in the third activity "Sensing Temperature" the question "Can you believe your senses?" is explored using temperature sensor allowing students to think about what would happen if they couldn't sense the difference between hot and cold.

Misconceptions

Misconceptions about how the senses work fall into several different categories. The first relates to how the human senses work. Children often believe that our senses work in isolation. We know that this is not true. Just try plugging your nose and closing your eyes and tasting a small piece of apple and a piece of onion and you will have a hard time distinguishing between the two. In addition students believe that all they see, hear, taste, smell, and feel is all there is. We know that they are all kinds of sensor inputs that the human sense can not pick up. The second has to do with animal senses. For example the idea that birds can smell if a person has touched their young and will reject them is general not true since most birds have a poor sense of smell (one exception is the vulture who can smell its next meal).

Learning Objectives

NGSS
- Performance Expectations
  - 4-LS1-2. Use a model to describe that animals receive different types of information through their senses, process the information in their brain, and respond to the information in different ways.
  - 4-LS1-1. Construct an argument that plants and animals have internal and external structures that function to support survival, growth, behavior, and reproduction.
  - 4-PS4-2. Develop a model to describe that light reflecting from objects and entering the eye allows objects to be seen.
  - 5-PS1-3. Make observations and measurements to identify materials based on their properties.
- Disciplinary Core Ideas
  - ES-LS1: From Molecules to Organisms: Structures and Processes
    - LS1.A: Structure and Function
      - Plants and animals have both internal and external structures that serve various functions in growth, survival, behavior, and reproduction. (4-LS1-1)
    - LS1.D: Information Processing
      - Different sense receptors are specialized for particular kinds of information, which may be then processed by the animal’s brain. Animals are able to use their perceptions and memories to guide their actions. (4-LS1-2)
  - ES-PS1: Matter and its Interactions
    - PS1.A: Structure and Properties of Matter
      - Measurements of a variety of properties can be used to identify materials. (Boundary: At this grade level, mass and weight are not distinguished, and no attempt is made to define the unseen particles or explain the atomic-scale mechanism of evaporation and condensation.) (5-PS1-3)
  - ES-PS4: Waves and Their Applications in Technologies for Information Transfer
    - PS4.B: Electromagnetic Radiation
      - An object can be seen when light reflected from its surface enters the eyes. (4-PS4-2)
- Practices
  - Developing and using models
    - Develop and/or use a model to predict and/or describe phenomena.
    - Develop and/or use a model to generate data to test ideas about phenomena in natural or designed systems, including those representing inputs and outputs, and those at unobservable scales.
  - Engaging in argument from evidence
    - Construct, use, and/or present an oral and written argument supported by empirical evidence and scientific reasoning to support or refute an explanation or a model for a phenomenon or a solution to a problem.
  - Planning and carrying out investigations
    - Collect data to produce data to serve as the basis for evidence to answer scientific questions or test design solutions under a range of conditions.
- Crosscutting Concepts
  - Patterns
    - Students recognize that macroscopic patterns are related to the nature of microscopic and atomic-level structure. They identify patterns in rates of change and other numerical relationships that provide information about natural and human designed systems. They use patterns to identify cause and effect relationships, and use graphs and charts to identify patterns in data.
  - Cause and effect
    - Students classify relationships as causal or correlational, and recognize that correlation does not necessarily imply causation. They use cause and effect relationships to predict phenomena in natural or designed systems. They also understand that phenomena may have more than one cause, and some cause and effect relationships in systems can only be described using probability.
  - Scale, proportion, and quantity
    - Students observe time, space, and energy phenomena at various scales using models to study systems that are too large or too small. They understand phenomena observed at one scale may not be observable at another scale, and the function of natural and designed systems may change with scale. They use proportional relationships (e.g., speed as the ratio of distance traveled to time taken) to gather information about the magnitude of properties and processes. They represent scientific relationships through the use of algebraic expressions and equations.
NSES
- Science as Inquiry - Understandings about scientific inquiry
  - Simple instruments, such as magnifiers, thermometers, and rulers, provide more information than scientists obtain using only their senses.
- Life Science - The characteristics of organisms
  - Each plant or animal has different structures that serve different functions in growth, survival, and reproduction. For example, humans have distinct body structures for walking, holding, seeing, and talking.
  - The behavior of individual organisms is influenced by internal cues (such as hunger) and by external cues (such as a change in the environment). Humans and other organisms have senses that help them detect internal and external cues.
- Physical Science - Properties of objects and materials
  - Objects have many observable properties, including size, weight, shape, color, temperature, and the ability to react with other substances. Those properties can be measured using tools, such as rulers, balances and thermometers.
- Physical Science - Light, heat, electricity, and magnetism
  - Light travels in a straight line until it strikes an object. Light can be reflected by a mirror, refracted by a lens, or absorbed by the object.

Discussion: Setting the Stage

What are some ways that we gather information about the world around us?

There are many ways that we gather information about the world around us. We can hear, see, smell, taste and feel things in the world around us. Our sense work together to help us understand the world and don't work alone.

Discussion: Formative Questions

Insect Sensors

What advantages might the size and multiple lenses give an insect?

The size which is large compared to body size in most insects allows for greater field of vision as do the multiple lenses. The disadvantage is that the multiple lenses do allow for clear detail of objects being seen since they are broken into thousands of individual pieces.
How is it similar to your eye? How is it different?

Answers will vary but might include their location on the head, number of lenses, lack of eye lids, etc. Measuring Different Colors in Light
Does the closeness of the sensor make a difference in the measurements you get?

The closer to the surface that is emitting the light the greater the lux number that is recorded. Sensing Temperature
Does the material make a difference in how you sense the temperature?

Answers may vary, but might include that things made of metal may feel warmer or colder depending on what they are being used for.

Discussion: Wrapping Up

Activity 1 - Insect Sensors

How does an insect find out about its environment?

Answers may include through sight with their eyes and touch with their antenna. Some students may also know that insects are able to taste, smell, and hear through various means that are different from humans.
Did you notice differences between the eyes of different insects you were able to look at?

Answers will vary. Depending on the type of insects they might have notices differences in the size and number of lenses in the eyes. They may also have seen other differences the body parts they observed. Activity 2 - Measuring Different Colors With Light
How might the ability to distinguish between colors help an animal survive?

Color may help animals tell the difference between foods that are edible and those that aren't. It may also be used to attract a mate. Activity 3 - Sensing Temperature
When you sweat you feel cooler. Why do you think this happens?

The moisture on the skin causes the body to feel cooler as it evaporates. This is because evaporation is an endothermic process that pulls heat away from the body making it feel cooler.

Additional Background

Most people don't think about insects being able to sense things like taste, smell, sound, etc. Insects though have a complex system that allows them to take advantage of all these senses (http://www.cals.ncsu.edu/course/ent425/tutorial/senses.html). They use some very different methods from humans. For example insect eyes have compound eyes. This means that their eyes are made up of many closely packed facets (think lenses). The number of facets varies by species. Some worker ants have as few as 6, while some dragonfly species may have more than 25,000.

In the activity "Measuring Different Colors with Light" it is important to understand that light is a form of energy. In this activity light is being measured in lux units which is an International Standard of measurement. A lux unit is the illuminance of 1 lumen per square meter of visible light. Light waves can either be reflected, absorbed, or transmitted.

In the activity "Sensing Temperature" it is important understand that temperature a measure of the average molecular motion in a system and is given in a standard unit, for example Fahrenheit or Celsius. Heat is the amount of energy in a system. In humans hot and cold are collected and transferred through specialized neurons starting near the skins surface to the brain.

Analysis

Insect Sensors

What parts of an insect did you look at that might have had sensors?

Answers may vary but should include the antennae, eyes, and body hair.
How do you think these parts help the insect find out about its environment?

Answers may vary but should include using the antennae to locate food and locate objects in their environment, their eyes to locate danger or food sources, or body hair that helps sense movement.

Measuring Different Colors With Light

Using your eye, did you put the colors in the same order as when you used the light sensor?

Student answers will vary, but they should be able to explain any similarities and differences.
Based on your light measurements, do you think the sensor can see color? Why or why not? Give examples.

Student answers will vary, but they may infer that the differences in lux values, may transfer to colors in general.
There are scientific instruments, such as telescopes and microscopes, that help our eyes to see more. What can you see with their help?

Student answers will vary, but they should talk about how telescopes allow us to see things that are far away, like far away ships or stars in the sky. Microscopes allow us to see things that are very small which we couldn't see without their help (cells) or things they we need help seeing details of like insect parts.
What do you know about eyes and light sensors? What questions do you still have?

Student answers will vary.

Sensing Temperature

Suppose you touched two things and it felt like they were different temperatures, but a thermometer measured the same temperature for both. Which would you believe, your finger or the thermometer? Explain your answer: "I would believe _____ because _______."

Answers may vary, but should include some explanation that talks about how we perceive temperature is not as accurate as using a tool like a thermometer.
Is moving air the same temperature as still air?

Moving air and still air will be the same temperature if all other variables are keep the same.
Why do you think moving air (unless it's very hot) makes your skin feel cooler?

Answers could include ideas about evaporation and/or perspiration.

Further Investigation

Here are some further questions students might choose to investigate

Insect Sensors

What are three ways that you sense your environment?

What do you think you would need to study to understand bugs?

Do you see any parts that look different from those on your first insect? Can you find any of the same parts? Describe some ways that the two different insects look different.

Measuring Different Colors With Light

How well can you walk around the classroom with a tissue over your eyes? Can you avoid running into things? Can you find your friend in a group of kids? Can you locate the windows? Can you seeing someone moving?

Sensing Temperature

Does rain make the air feel warmer or cooler? Why do you think this happens?