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Public Release Item Scoring Information Return

Goal 3 Concepts Of Biology

Expectation 3.3 The student will analyze how traits are inherited and passed on from one generation to another.

Indicator 3.3.2 The student will illustrate and explain how expressed traits are passed from parent to offspring.

Assessment Limits:

  • phenotypes (expression of inherited characteristics)
  • dominant and recessive traits
  • sex-linked traits (X-linked only; recessive phenotypes are more often expressed in the male)
  • genotypes (represented by heterozygous and homozygous pairs of alleles)
  • punnett square (use to predict and/or interpret the results of a genetic cross; translate genotypes into phenotypes - monohybrid only)
  • Pedigree (use to interpret patterns of inheritance within a family)

Brief Constructed Response (BCR) Item - Released in 2008

A scientist wants to determine the genotype of a black female rabbit. She knows that the allele for black fur (B) is dominant to the allele for brown fur (b) and is not sex-linked. The scientist performs a cross with a brown male rabbit to try to determine the genotype of the female rabbit.

Complete the following steps to determine if the black female rabbit is homozygous or heterozygous for fur color.

  • Identify the two possible genotypes of the female rabbit.
  • Complete two Punnett squares using the possible genotypes of the parent rabbits to show the expected offspring.
  • Explain how the fur color of the offspring would help the scientist determine the genotype of the female rabbit.

Write your answer in your Answer Book.

The following 8 Anchor Papers represent a range of score points and are used in conjunction with the rubric to assess student responses.

Anchor Paper #1

image of student response

Score for Anchor Paper #1: Rubric Score 1

Annotation: This response demonstrates some understanding of the question. The Punnett square for the homozygous female (BB × bb) is correctly completed. The Punnett square for the heterozygous female is incorrect, as it shows a cross between two heterozygous parents (Bb × Bb) instead of a cross between a heterozygous female and a homozygous recessive male (Bb × bb). A general explanation for how the fur color of the offspring would help determine the female’s genotype (If the fur color of the offspring is black … either homozygous or heterozygous; brown, then the scientist will know … heterozygous) is provided. The explanation includes a vague reference to the possible genotypes of the female rabbit (homozygous or heterozygous dominant). The supporting details are minimally effective.


Anchor Paper #2

image of student response

Score for Anchor Paper #2: Rubric Score 1

Annotation: This response demonstrates some understanding of the question. The two possible genotypes for the female rabbit (BB or Bb) are identified. A correctly completed Punnett square for the heterozygous female (bb × Bb) is provided, but the Punnett square for the homozygous female is incorrect, as it shows a cross between a homozygous dominant rabbit and a heterozygous rabbit (BB × Bb) instead of a cross between a homozygous dominant rabbit and homozygous recessive rabbit (BB × bb). The supporting details are minimally effective throughout.


Anchor Paper #3

image of student response

Score for Anchor Paper #3: Rubric Score 2

Annotation: This response demonstrates a basic understanding of the question. The student identifies one possible genotype of the female (Bb-heterozygous black) and provides two correct Punnett squares in the appropriate boxes. The explanation for how the fur color of the offspring would help the scientists determine the female’s genotype is adequate (has to be heterozygous so she can have variation in her offspring; homozygous then they would all be the same). Overall, the supporting details are adequate.


Anchor Paper #4

image of student response

Score for Anchor Paper #4: Rubric Score 2

Annotation: This response demonstrates a basic understanding of the question. Although the possible genotypes of the female are not identified, the student provides correct Punnett squares for the homozygous and heterozygous female in the appropriate boxes. The explanation for how the fur color of the offspring would help determine the genotype of the female rabbit is adequate (the only way that these to rabbits could have brown babies was if the mother was heterozygous hence if they had brown babies we would know the genotypes). The supporting details are adequate.


Anchor Paper #5

image of student response

Score for Anchor Paper #5: Rubric Score 3

Annotation: This response demonstrates a good understanding of the question. The two possible genotypes of the female rabbit are identified (homozygous black ... BB, or heterozygous black … Bb). Two correct Punnett squares, in the appropriate boxes, are provided. The explanation given by the student addresses each possible outcome in terms of how the color of the offspring would help scientists determine the female’s genotype (If the offspring are all black, then the mother is homozygous) and shows a synthesis of information (If half of the offspring are black and half are brown, or is any are brown at all, then … heterozygous). Overall, the supporting details are generally complete.


Anchor Paper #6

image of student response

Score for Anchor Paper #6: Rubric Score 3

Annotation: This response demonstrates a good understanding of the question. The two possible genotypes of the female rabbit (BB or Bb) are identified. The Punnett squares are correct and in the appropriate boxes. The last part of the question demonstrates synthesis as the student provides an explanation for what color fur the offspring would have with each of the possible genotypes (if she were homozygous dominant each of her offspring would have to have dominant black fur; If any of her offspring had brown fur, scientist would no that she has a heterozygous dominant gene because 50 percent … brown fur). The supporting details are generally complete.


Anchor Paper #7

image of student response

Score for Anchor Paper #7: Rubric Score 4

Annotation: This response demonstrates a full and complete understanding of the question. The student identifies the possible genotypes of the female (BB; Bb) and provides two correct Punnett squares. Details are integrated throughout the response, as the results in the Punnett squares support the explanation of how the fur color of the offspring would help determine the female’s genotype (According to the Punnett squares she could have offspring that are all heterozygous … or … ½ the offspring were heterozygous black and half were brown). A full synthesis of information is demonstrated, as the student further explains how to determine the female’s genotype (If she doesn’t have that gene [BB] none of her offspring could have brown fur). The use of accurate scientific terminology (test cross; varience; phenotype) enhances the response.


Anchor Paper #8

image of student response

Score for Anchor Paper #8: Rubric Score 4

Annotation: This response demonstrates a full and complete understanding of the question. The Punnett squares are correct and in the appropriate boxes. The student integrates a pertinent description of inheritance (sexually produced offspring must have one gene from each parent) into a full explanation of how the fur color of the offspring would help determine the females genotype (if any of the offspring … brown, that would mean that they would be bb, and therefore would have gotten a “b” from the female, which would have made her heterozygous or Bb; Since the offspring would automatically receive a “b” from the brown parent, it would be known that since the offspring entirely was black that the female would had to of given the offspring a “B,” and if it happened every time … BB). The possible genotypes of the female are identified in the explanation. The use of accurate scientific terminology (sexually produced offspring; test cross) enhances the response and the supporting details are pertinent and complete.


Brief Constructed Response (BCR) Rubric

Print: Scoring Rubric (pdf)
Score 4

There is evidence in this response that the student has a full and complete understanding of the question or problem.

  • Pertinent and complete supporting details demonstrate an integration of ideas.
  • The use of accurate scientific terminology enhances the response.
  • An effective application of the concept to a practical problem or real-world situation reveals an insight into scientific principles.*
  • The response reflects a complete synthesis of information.
Score 3

There is evidence in this response that the student has a good understanding of the question or problem.

  • The supporting details are generally complete.
  • The use of accurate scientific terminology strengthens the response.
  • The concept has been applied to a practical problem or real-world situation.*
  • The response reflects some synthesis of information.
Score 2

There is evidence in this response that the student has a basic understanding of the question or problem.

  • The supporting details are adequate.
  • The use of accurate scientific terminology may be present in the response.
  • The application of the concept to a practical problem or real-world situation is inadequate.*
  • The response provides little or no synthesis of information.
Score 1

There is evidence in this response that the student has some understanding of the question or problem.

  • The supporting details are only minimally effective.
  • The use of accurate scientific terminology is not present in the response.
  • The application, if attempted, is irrelevant.*
  • The response addresses the question.
Score 0

There is evidence that the student has no understanding of the question or problem.

  • The response is completely incorrect or irrelevant or there is no response.

* On the High School Assessment, the application of a concept to a practical problem or real-world situation will be scored when it is required in the response and requested in the item stem.

Updated 2002

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