Gold Seal Lesson:
Preparing Yeast Cell Cultures

Copernicus Education Gateway

Subject:

Science

Grade:

9-12

ICLE Standards:

Mathematics:
Mathematical Connections - Use and value the connections between mathematics and other disciplines.
Functions - Represent and analyze relationships using tables, verbal rules, equations, and graphs.
Statistics - Construct and draw inferences.

Science:
Science as Inquiry - Develop the abilities of scientific inquiry.

Performance Task:

Jeff works as a lab technician for a company that manufactures household cleaning products. One of the products being considered for market is a household chemical that kills yeast, mold, and mildew. To better understand these types of cells, Jeff must find the conditions under which these cells grow best.

In order to find out about yeast, Jeff prepared three yeast solutions using equal amounts of yeast and water.

He placed the three solutions in containers labeled A, B, and C and added 10 ml of a sucrose solution to each container as follows:

• 10% sucrose solution to container A
• 25% sucrose solution to container B
• 50% sucrose solution to container C.

Jeff placed all three solutions in a warm place. He prepared a wet mount microscope slide from each solution every 24 hours for five days and counted the yeast cells in one field of view using the high power lens. The results are recorded in the table below.

1. Prepare a line graph of the data from the table above. Place days on the x-axis and solution percentage on the y-axis.
2. Write a brief and concise report being sure to include:

1. Two conclusions using the line graphs drawn from the given data
2. Other variables that may effect the population growth of yeast cells
3. An evaluation of the method used by Jeff to obtain his data
4. Any adjustments that you might make in the experiment

Knowledge / Skills:

Understand the concepts and uses of matrices in modeling (i.e., finite graphs (structures) can be represented geometrically and interpreted algebraically in the form of a matrix).  (m51)

Know the components and properties of the rectangular coordinate system, (i.e., x - y axis, origin, quadrants, abscissa (x-coordinate) and ordinate (y-coordinate), and the general representation of a point (x,y)).  (m23)

Know and apply the principles of scientific inquiry.  (s114)

Understand the concepts and uses of matrices in modeling (i.e., finite graphs (structures) can be represented geometrically and interpreted algebraically in the form of a matrix).  (ela40)

Rubric:

4 Points  =  The student makes a complete response to all parts of the task. The line graph constructed is accurate and legible. He/she makes two reasonable conclusions based on the constructed graph. The evaluation of the experimental design is reasonable and well stated. The written report is well composed and includes responses to all parts of the performance task.

3 Points  =  The students needs some coaching to make a complete response to all parts of the task. The line graph is not neatly constructed, but seems to be accurate. Only one conclusion based on the constructed graph is made. The student has difficulty expressing his/her evaluation of the experimental design. The written report includes responses to all parts of the performance task, but is not very well written.

2 Points  =  The student makes only a partial response to all parts of the task. The line graph has inaccuracies and is not legible. The student is unable to make any reasonable conclusion based on the constructed graph. He/she does not have a good understanding of experimental design and is not able to make any meaningful evaluation of it. The written report is incomplete and poorly written.

1 Point  =  The student does not complete the task. The line graph contains several inaccuracies or is not constructed at all. No conclusions based on a constructed graph are made. The student appears to have no idea of experimental design. The written report is sketchy at best, and contains little, if any,
worthwhile information.

Keywords:

SCIENTIFIC CONCEPT
GENERAL SCIENCES
SCIENTIFIC INQUIRY

Grades:

Kg [] - 1 [] - 2 [] - 3 [] - 4 [] - 5 [] - 6 [] - 7 [] - 8 [] - 9 [X] - 10 [X] - 11 [X] - 12 [X]

ICLE Application:

D

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