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A pedigree chart shows a family where a genetic trait is inherited. The trait is recessive. Squares represent males, circles represent females, shaded symbols indicate individuals with the trait, and unshaded symbols indicate individuals without the trait.
Diagram Description
Pedigree Chart
Generation 1: Two unshaded parents (one male, one female). Generation 2: Four children: one shaded male, one unshaded female, one unshaded male, one unshaded female. Generation 3: The shaded male from generation 2 marries an unshaded female. They have two children: both unshaded (one male, one female).
| Generation | Individual | Sex | Trait |
|---|---|---|---|
| 1 | Parents | Male | No trait |
| 1 | Parents | Female | No trait |
| 2 | Child 1 | Male | Has trait |
| 2 | Child 2 | Female | No trait |
| 2 | Child 3 | Male | No trait |
| 2 | Child 4 | Female | No trait |
| 3 | Child 1 | Male | No trait |
| 3 | Child 2 | Female | No trait |
- a[1]
Identify What type of inheritance pattern does this pedigree chart show?
Aim for approximately 1 distinct marking point.
- b[2]
State Why can two parents without the trait have a child with the trait?
Aim for approximately 2 distinct marking points.
0 of 2 parts answered
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