Looking at the pedigree chart labeled “Pedigree #1”:
- The top row (generation I) has two parents: a shaded square (affected male) and an unshaded circle (unaffected female).
- They have four children in generation II: one shaded square (affected male), and three unshaded circles (unaffected females).
We are asked to count how many males and females are affected.
Step-by-step:
1. In pedigree charts:
- Squares = males
- Circles = females
- Shaded = affected by the trait
- Unshaded = not affected
2. Look at all shaded symbols:
- Generation I: one shaded square → that’s 1 affected male.
- Generation II: one shaded square → that’s 1 more affected male.
- No shaded circles anywhere → no affected females.
3. So total affected males = 2
Total affected females = 0
Now check the answer choices:
a. 2 affected males? YES → T
b. 2 affected females? NO → F
c. 3 affected males? NO → F
d. 2 affected females? NO → F
e. 1 affected male? NO → F
f. 0 affected females? YES → T
So correct answers are: a = T, f = T
Final Answer:
a. T
b. F
c. F
d. F
e. F
f. T
Parent Tip: Review the logic above to help your child master the concept of genetics pedigree worksheet.
