Publication No. 10248
Student Laboratory Kit
Materials Included In Kit
Colored marker pins (push pins), 20
Caution students about use of marker pins. The kernels are hard and pins cannot be easily inserted into the kernels. Pins should be inserted into the soft corn cob tissue of each ear.
Please consult your current Flinn Scientific Catalog/Reference Manual for general guidelines and specific procedures, and review all federal, state and local regulations that may apply, before proceeding. All materials from this activity can be reused.
Correlation to Next Generation Science Standards (NGSS)†
Science & Engineering PracticesAsking questions and defining problems
Developing and using models
Planning and carrying out investigations
Analyzing and interpreting data
Using mathematics and computational thinking
Engaging in argument from evidence
Obtaining, evaluation, and communicating information
Disciplinary Core IdeasMS-LS3.A: Inheritance of Traits
MS-LS3.B: Variation of Traits
HS-LS3.A: Inheritance of Traits
HS-LS3.B: Variation of Traits
Scale, proportion, and quantity
Systems and system models
MS-LS3-2. Develop and use a model to describe why asexual reproduction results in offspring with identical genetic information and sexual reproduction results in offspring with genetic variation.
II. Actual Count
Answers to Questions
As we all know, it is common to find yellow corn kernels. Purple corn kernels are not nearly as common! The study of corn kernel color illustrates colored basic genetic principles.
Each corn kernel on an ear of corn is a separate offspring resulting from a cross between a female parent (of which the ear and the corn cob are a part) and a male parent, which supplied the pollen grains that fertilized the egg. The fertilized egg then grew into the corn kernels (seeds). The colored layer of the seed that is visible is a part of the endosperm. If the endosperm is colored, it is observable. If the endosperm is not pigmented (colorless), the yellow color of the inner tissue shows through, and the color appears as yellow, white or cream.
The plant breeder next made two kinds of crosses that produced the ears of corn used in this laboratory. The first cross involved crossing two of the first generation offspring (RrSs x RrSs). The second cross (often called a back cross) involved crossing a first generation offspring with one of the original non-purple offspring (RrSs x rrss).
Colored marker pin
Use caution when working with the marker pins. Do not pierce the corn kernels with the pins—push them into the soft corn cob tissue. Do not remove any corn kernels from the ear.
Student Worksheet PDF