Science
Strand III
Use Scientific Knowledge from the Life Sciences in Real-World Contexts

 

Science/Strand III
Content Standard 3
All students will investigate and explain how characteristics of living things are passed on through generations; explain why organisms within a species are different from one another; and explain how new traits can be established by changing or manipulating genes. (Heredity)

 

Science/Strand III/Content Standard 3
Middle School

 

Science/Strand III/Content Standard 3/Middle School
Benchmark 2
Describe how heredity and environment may influence/determine characteristics of an organism.

Benchmark Clarification

Inherited traits are those present in the genetic makeup of an organism that have been passed on from one generation to the next. These may include:

  • Eye color
  • Left- or right-handedness
  • Butterfly wing patterns
  • Animal fur color

Acquired traits develop or occur after an organism is born. They occur in response to environmental factors such as stress, overall health, nutritional choices, chemical exposure, and changes in land use and are not a result of the organism’s genetic code. These include:

  • Straightened teeth from wearing braces
  • The loss of a limb in an accident

Students will:

  • Distinguish between inherited traits and acquired traits

Key Concept / Real World Context / Instructional Example / Assessment Example / Resources

 

Science/Strand III/Content Standard 3/Middle School/Benchmark 2
Key Concept
Traits:

  • inherited
  • acquired

 

Science/Strand III/Content Standard 3/Middle School/Benchmark 2
Real World Context
Data on heredity, such as:

  • identical twin studies
  • effects of introduced toxins
  • effects of natural selection
  • effects of controlled selection and breeding

 

Science/Strand III/Content Standard 3/Middle School/Benchmark 2
Instructional Example

Benchmark Question: In what ways do living things adapt to survive in their environments?

Focus Question: How do inherited traits allow organisms to become better adapted to their environments?

The teacher will ask the class to consider the following general questions:

1. What changes can take place in an island ecosystem?

2. How might these changes affect the process of natural selection?

3. Which inherited traits might be passed on from generation to generation?

4. Looking ahead, what other events may cause an organism to adapt over time?

The teacher will present the students with the following scenario:

Pretend that you are a scientist in the year 2020. You observe that a longer grass has invaded an island. How might a ladybug population living on this island adapt to this change in environment? Consider the following traits: body color, exoskeleton hardness, size of wings, length of legs, etc.

In small groups, students will write predictions about the adaptations they think might occur in order for the ladybug population to survive. Each student will justify his or her predictions and present his or her reasons in chart form. Use a chart with the headings: ADAPTATION, REASON.

Constructing: (SCI.I.1.MS.1).

Reflecting: (SCI.II.1.MS.5).

 

Science/Strand III/Content Standard 3/Middle School/Benchmark 2
Assessment Example

Students will construct a model that shows the traits that a futuristic insect might acquire as a result of a current environmental change.

Students will present their models to the class and explain their answers to the following questions:

  • Why did the insect acquire those traits?
  • What two changes did the insect undergo?
  • What factors might have influenced natural selection?
  • What traits might be passed on from this insect to its future offspring to ensure reproductive success?

(Give students rubric before activity.)

Scoring Rubric

Criteria

Apprentice

Basic

Meets

Exceeds

Accuracy of model

Develops a model showing inaccurate traits of a futuristic insect.

Develops a model that shows the traits of a futuristic insect.

Develops an accurate model that clearly shows the traits of a futuristic insect.

Develops an in-depth, accurate model that clearly shows the traits of a futuristic insect.

Presentation of model

Presents information in an incomplete, difficult to understand manner.

Presents information in an easy to understand manner.

Presents information in an interesting, easy to understand, creative manner.

Presents information in an interesting, easy to understand, creative manner with additional visuals.

 

Science/Strand III/Content Standard 3/Middle School/Benchmark 2
Resources

Webliography.
http://mtn.merit.edu/mcf/SCI.III.3.MS.2.html

Mader, Sylvia. Inquiry Into Life with ESP CD-ROM and E-text CD-ROM.
McGraw Hill, 2000.

Murphy, Pat. “Cells and Heredity,” SCIENCE EXPLORER: Family Experiments from the World’s Favorite Hands-On Museum. Owlet, 1996.