Bio 10-Dr. Cunninghum Genctics Worksheet 3. For each phenotype below, list the genotypes (remember to use the letter of the dominant trait) Straight hair is dominant to curly. __ straight __ curly Pointed heads are dominant to round heads. __ pointed __ round

## Step 1<br />In genetics, traits are determined by genes. Each gene has two alleles, one from each parent. The dominant allele is represented by a capital letter, while the recessive allele is represented by a lowercase letter.<br /><br />## Step 2<br />In this problem, straight hair and pointed heads are dominant traits. This means that if an individual has at least one allele for straight hair or pointed heads, they will exhibit these traits.<br /><br />## Step 3<br />For straight hair, the possible genotypes are SS (homozygous dominant) or Ss (heterozygous). Both of these genotypes will result in the phenotype of straight hair.<br /><br />## Step 4<br />For curly hair, the only possible genotype is ss (homozygous recessive). This is because curly hair is a recessive trait, and an individual must have two copies of the recessive allele to exhibit this trait.<br /><br />## Step 5<br />Similarly, for pointed heads, the possible genotypes are PP (homozygous dominant) or Pp (heterozygous). Both of these genotypes will result in the phenotype of pointed heads.<br /><br />## Step 6<br />For round heads, the only possible genotype is pp (homozygous recessive). This is because round heads are a recessive trait, and an individual must have two copies of the recessive allele to exhibit this trait.