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Learning Objectives 

Students will: 

• Grow yeast and observe the results through a microscope.
• Describe through drawings and words what they observe in a microscope.
• Conduct an experiment that compares the growth of yeast cells in warm and cold water.
• Quantify the results of their experiments.
• Analyze the features of scientific illustrations.
• Create an original scientific illustration. 
• Present original work to an audience.

Standards Alignment

National Core Arts StandardsNational Core Arts Standards

Common Core State StandardsCommon Core State Standards

Next Generation Science StandardsNext Generation Science Standards

Recommended Student Materials

Editable Documents: Before sharing these resources with students, you must first save them to your Google account by opening them, and selecting “Make a copy” from the File menu. Check out Sharing Tips or Instructional Benefits when implementing Google Docs and Google Slides with students.

Videos

Additional Materials

• Drawing paper, pencils, hand lens (optional)
• Microscope
• Tap water, jelly jar, sugar, yeast, markers, masking tape
• Heat source: incubator or stove

Teacher Background

Teachers should have a clear understanding of reproduction at the cellular level. Teachers should review the article, , prior to teaching the lesson. 

Student Prerequisites 

Students should have background knowledge on plants and animal cells and the basics of using a microscope.

Accessibility Notes

Modify handouts, text, and utilize assistive technologies as needed. Provide preferential seating for visual presentations and allow extra time for task completion.

Engage

1. Show students two scientific drawings of an animal cell from the presentation, Ask students: As a scientist, what do you notice about the drawing? As an artist, what do you notice? How does the study of science and the creation of art merge in this drawing?

2. Ask students to practice drawing with accuracy by sketching a part of a hand. If hand lenses are available, distribute them to students or pairs of students. Ask students to look closely at one part of their hands (or their partner’s hand), such as the knuckle or fingernail. Have students sketch what they see, with as much detail and accuracy as possible. When finished, allow students to share and discuss their sketches, talking about techniques they used and any difficulties they encountered.

3. Discuss how this process of drawing is different from other kinds of drawing students have experienced: cartooning, doodling, illustration of stories, etc. For examples of scientific illustrations and the techniques employed to create them, have students explore the images more closely from the presentation,

4. Make a list as a class of the characteristics of scientific illustrations. Discuss with students the fact that in science, drawing is used to communicate ideas and information. In order for others to interpret the information correctly, a scientific drawing must be highly detailed, accurate, appropriately scaled and colored, and clearly labeled. Scientific drawing requires that students create an accurate, true reflection of the phenomenon or object being observed.

Build

1. Introduce students to cell reproduction. Show the video, Lead a discussion on mitosis and the essential functions of living organisms (growth, reproduction, response to stimuli, movement, nutrition, excretion, respiration). Review reproduction among plants or animals. Discuss what is necessary for reproduction to be possible, leading students to understand that the other functions of living organisms are required for reproduction.

2. Break the class into small groups or pairs. Tell students they are going to explore the science and art of mitosis with a yeast experiment. Assign each small group or pair of students to a workstation. (Set up in advance with the supplies listed above.) Tell students that during the experiment, they will need to record concepts and details about the yeast in order to create an illustration at the end of the lesson. Ask students: As you make observations, what would a scientist note? What would an artist note? 

3. Instruct each group to make a sugar solution for the yeast. Display or distribute the instructions. You may also model the steps in front of the class. Fill each jelly jar with one cup of warm tap water, and dissolve 1 1⁄2 tablespoons of sugar into the water, creating a solution. Dissolve 1 teaspoon of yeast into the sugar solution. Stir gently.

4. Have the students make slides of the solution. It is a good idea to model this procedure as you explain the steps. Using an eyedropper, place a few drops of the solution on a clean slide. Cover the drops with a coverslip and place the slides under a microscope. Assist students with the focus feature on the microscope. Begin viewing under a low magnification and move to high. Once the yeast cells become visible, the students should describe with words and draw what they see in their science journals. The students should also count the number of cells they see and jot that number down in their journals.

5. Cover and label the jars of solution. Have each group or pair label their jelly jars with their names and the word “cold” or “warm” using markers and masking tape. Store the “cold” solution in a refrigerator and the “warm” solution in a warm place, such as an incubator or inside a stove set on low. The temperature in the warm place should be set between 98 and 100 degrees Fahrenheit. Let all of the solutions sit for 24-48 hours.

6. Have each group write a hypothesis predicting which jar of yeast will yield more buds (new cells) - the yeast stored in the refrigerator or the yeast stored in the warm place. The students must state the reasons for their hypotheses.

Apply

1. Have students examine their solutions. After 24-48 hours, set up the students’ tables with their labeled yeast solutions, four slides, four slide covers, microscopes, and the students’ science journals. Have each group examine the cold and warm samples under a microscope.

2. Have students gather, tabulate, analyze and compare their data. Pairs or small groups should discuss whether the results confirm or disconfirm their hypotheses. What was their original hypothesis? Was the hypothesis correct? How did the two samples compare?

3. Discuss the career of scientific illustration. Point out that there are many careers that bring together the arts and other disciplines. One field that brings together art and science is scientific illustration. This field requires that an artist possess not only strong artistic skills, but also high attention to detail, the ability to visualize and interpret information, and the ability to calculate and draw images to scale. Discuss some of the techniques required for accurate scientific illustration, as well as ways in which these drawings would be useful to scientists and to the public at large. Some points to consider in the discussion:

What role has scientific illustration had in transmitting knowledge throughout history?

- What role has it played in recording changes in scientific understanding over time?

- What role does creativity play in scientific illustration?

- Though the focus in the scientific illustration is on the accurate visual depiction of an object or phenomenon, is there any interpretation made by the artist?

- Is there any art that is truly objective, or is all art subjective to some extent?

- How much scientific background would a scientific illustrator need?

4. Share and review the resource with students. Tell students they are going to create an original scientific drawing. Remind students of the drawings they observed earlier in the lesson and encourage the same level of detail and accuracy. Distribute art supplies or have students create digital drawings. 

5. Write an artist statement that effectively relates their data and conclusions to their target audience: the class as a whole. Encourage students to describe elements of their drawing that relate to their scientific data. 

Reflect 

1. Display students’ drawings and artist statements. Invite another class to participate in a gallery walk to observe the scientific drawings. Students should be prepared to speak about the topic both scientifically and artistically.

2. Discuss the experimental results. Go over the results of the experiments. In general, groups should have very similar results; if there are any surprises, discuss possible reasons for the differing results (for example, excessively hot water might kill yeast during the creation of the solution), and consider what further experiments could be made to test the hypotheses developed in the discussion. Draw a conclusion, as a class, about the effects of heat on reproduction in yeast.