Using the provided pedigree chart, answer the following questions about fleece length in sheep: identify dominant/recessive traits, determine genotypes and phenotypes, and explain sources of variation

4.5.1
The characteristic that is dominant is Long fleece.

4.5.2
Individual 5 has short fleece, which is the recessive trait. Therefore, its genotype is ll.

4.5.3
Individual 9 is a shaded circle, indicating a female with long fleece. Its phenotype is Long fleece.

4.5.4
Individual 8 has long fleece (dominant trait). Its parents are individual 4 (long fleece) and individual 5 (short fleece, ll). Individual 4 also produced individual 7, who has short fleece (ll). For individual 7 to have short fleece, it must have inherited an l allele from individual 4. Therefore, individual 4 must be heterozygous (Ll). Individual 8 inherited an L allele from individual 4 and an l allele from individual 5. Thus, individual 8's genotype is Ll, making it heterozygous.

4.5.5
Female animals are represented by circles. Homozygous recessive individuals have short fleece (unshaded).

• Individual 1 (unshaded circle) is homozygous recessive.
• Individual 7 (unshaded circle) is homozygous recessive. There are 2 female animals that are homozygous recessive.

4.6.1
Variation refers to the differences in characteristics or traits among individuals within a population or species.

4.6.2
Two causes of variation are:

• Mutation
• Meiosis (e.g., crossing over, independent assortment)

4.6.3
One type of mutagen is UV radiation.