Score Level 1 Anchor Paper

This response demonstrates some understanding of the question. The Punnett square is correct. The probability of the child having a widow's peak is incorrect (chance that their child will have a widow's peak is 50%). The remainder of the response is unclear. The supporting details are only minimally effective.

Score Level 1 Anchor Paper

This response demonstrates some understanding of the question. The Punnett square is incorrect. The probability of the child having a widow's peak is correct (The phenotype would be 4/4 chance of having a widow's peak). Some understanding of DNA is shown (putting together the mother and father's DNA to see what it comes out for the child). The supporting details are only minimally effective.

Score Level 2 Anchor Paper

This response demonstrates a basic understanding of the question. The Punnett square is correct. The student correctly infers the parents' phenotypes (both have widows peak) and lists their genotypes (HH; Hh), mislabeling them as phenotypes. The child's chance of having a widow's peak is correct (100%). The genotype (HH or Hh) is correct and includes supporting detail (50% chance of having HH to Hh). The explanation of how DNA determines a trait is adequate (chromosomes on the DNA that are pasted from parents to offspring; one chromosome from mom and one from dad therefore determining traits). Overall, the response contains adequate supporting details.

Score Level 2 Anchor Paper

This response demonstrates a basic understanding of the question. The Punnett square is correct. The parents are clearly and correctly discussed (her genotype must be HH; he must have a widow's peak and a genotype of Hh). The child's genotype possibilities are correct (50 percent chance of being homozygous dominant with an HH genotype; 50 percent chance of being heterozygous with an Hh genotype). Although the child's phenotype is not specified, the student has demonstrated understanding of the terms "homozygous dominant" and "heterozygous" as applied to the parents and uses them correctly in describing the child. The DNA explanation is adequate (DNA determines these traits because it carries the genetic code that determines chemical combinations). Supporting details remain adequate.

Score Level 3 Anchor Paper

This response demonstrates a good understanding of the question. The Punnett square is correct. The parents are completely described (mother is homozygous dominant so she is HH; the father is heterozygous so he is Hh; both display the widows peak phenotype). The child's genotypes are specified (Hh or HH) and the child's probability of having a widow's peak is correct (either way he/she would have a widows peak). The explanation of how DNA determines a trait shows some synthesis (nucleotide pairs that code for genes; genes are mixed so that each [organism] passes an allele on; that allele combination determines a trait). Scientific terminology (nucleotide pairs; allele) strengthens the response.

Score Level 3 Anchor Paper

This response demonstrates a good understanding of the question. The Punnett square is correct. The parents are completely described (father with the genotype Hh and a phenotype of having the widow's peak; mother with a genotype of HH and also a phenotype of having the peak). The child's probability of having a widow's peak is correct (100% probability of their offspring having a widow's peak). The child's genotypes are specified (homozygous or heterozygous dominant). The student explains how genes determine the widow's peak trait, including some scientific terminology (produce a gamete) and showing synthesis (mother's genotype will produce gametes that all carry the trait. Since it is dominant, every possible combination of gametes … results in a child with a phenotype of having the trait).

Score Level 4 Anchor Paper

This response demonstrates a full and complete understanding of the question. The Punnett square is correct. The parents' genotypes are correctly specified (HH; Hh). The probability that the child will have a widow's peak is correct (100% likely to have widows peak). The possible genotypes for the child are correct (50% chance that the child will be homozygous for widow's peak [HH] and a 50% chance the child will be heterozygous for widow's peak [Hh]). The explanation of how DNA determines a trait is enhanced by scientific terminology (Chromosomes contain many strands of DNA. A part of each strand relates to a specific gene, for instance, widow's peak). The student further explains the expression of the trait (If there is one combination the individual may have widow's peak. If there is another combination the individual may not have widow's peak). All parts of the question are answered with pertinent details.

Score Level 4 Anchor Paper

This response demonstrates a full and complete understanding of the question. The Punnett square is correct. The parents' genotypes and phenotypes are fully described (mother of the child for widow's peak is dominant HH; phenotype is a widow's peak; father's genotype is Hh; he will have a widow's peak). A full and correct explanation, including synthesis, for these results is given (due to the fact that she is homozygous for that trait; due to the fact that he is heterozygous for a widow's peak; he will have a widow's peak as a phenotype because H is the dominant allele over the recessive h). The possible genotypes and phenotypes of the child are completely described (two possible genotypes of the child are HH [homozygous] or Hh [heterozygous]; he/she will have a widow's peak). Synthesis and additional details are provided (because of having genotypes with the dominant allele [H]). An explanation of how DNA determines a trait is pertinent and demonstrates an integration of ideas in the response (DNA determines a trait such as widow's peak during meiosis. The child inherits the trait during the transfer of chromosomes. When the DNA is made, it codes for all of the traits by making specific proteins which give the phenotype).