Enter your Name:   Enter your E-mail Address:  01a. Define True breeding 01b. Define Allele 01c. Define Homozygous genotype 01d. Define Heterozygous genotype 01e. Define Recessive allele 01f. Define Monohybrid cross 01g. Define Dihybrid cross 01h. Define Autosomal inheritance 02. State the principles of Mendelian genetics. 03. In humans, the ability to roll one's tongue is a dominant genetic trait. If "R" represents this allele and "r" represents the recessive allele, what are the possible genotypes for a man who can roll his tongue? 04. For a given trait, how many alleles does a normal gamete have? 05. For a given trait, how many alleles does a non-gamete cell have? 06a. The ability for a person to taste PTC is a dominant genetic trait ("T"), while the inability to taste PTC is recessive ("t"). If a man is heterozygous in that trait, what is his genotype? 06b. If a woman cannot taste PTC, what is her genotype? 06c. Draw the Punnett square for the children of this man and woman. 07. The following pedigree is for humans, concentrating on the ability to roll their tongues. Since you already know that the ability to roll tongues is dominant and the inability is recessive, determine whether the filled circles and squares represent those who can or those who cannot roll their tongues. 08a. A pea plant is heterozygous in both the color of the pea produced ("Y" or "y") and the height of the plant ("T" or "t"). What possible combinations of alleles exist in its gametes? 08b. A pea plant is heterozygous in both the color of the pea produced ("Y" or "y") and the height of the plant ("T" or "t"). Draw the resulting Punnett square for when this plant is self-pollinated. 08c. In this situation, what are the possible phenotypes and their percent chances? 09. Why do recessive phenotypes in sex-linked traits show up in males significantly more often than in females? 10a. Hemophilia is a sex-linked, recessive trait. Write the Punnett square for a non-hemophilic man having children with a woman who carries but does not have the disease. 10b. In this situation, what percent of girls will have the disease? 10c. In this situation, what percent of boys will have the disease? 11. Why would you not expect twins (who have identical DNA) to be identical in every way? 12. Name four means by which genetic disorders arise.