Heredity: Vocab and Punnett Squares

Matching Match the term with the correct definition Genotype The type of genes or alleles present in an organism; represented as letters (ex: Tt or RR) Dominant An allele that is always expressed in a phenotype; represented by an uppercase letter Alleles Different forms of the same gene (ex: tall vs. short) Gene The basic unit of heredity; part of a chromosome Matching Match the term with the correct definition. Phenotype the physical appearance of an organism (ex. Tall, curly hair) Recessive An allele that is only expressed when no dominant allele is present; represented by a lowercase letter Homozygous Having two of the same allele; a purebred (ex. TT or tt) Heterozygous Having two different alleles; a hybrid (ex. Tt) Just because the vocabulary in this unit is so important, how about some more vocab practice! A gene is the basic unit of heredity, a tiny part of a chromosome, it codes for a traitAlleles are different versions of genes (example: purple versus white flower color)When the two alleles in a pair are identical (example: TT or tt), the genotype is said to be homozygousWhen the two alleles in a pair are different (example: Tt), the genotype is said to be heterozygousA recessive allele is an allele whose effects are hidden by a dominant allele, represented with a lower-case letter.A genotypeis the different alleles an organism has, which are represented by upper and lowercase letters.A phenotype is the physical appearance of an organism, represented by descriptions. For each genotype, indicate whether it is heterozygous (HE) or homozygous (HO). Note: for your answers, simply type in HE or HO. Genotype HE AA HO Ee HE Hh HE LL HO bb HO Qq HE Phenotype practice - For each of the genotypes, determine the phenotype. In pea plants purple flowers (P) are dominant to white flowers (p). Indicate the phenotype by typing either purple or white for each blank below. Genotype Phenotype PP purple Pp purple pp white In pea plants yellow seeds (Y) are dominant to green seeds (y). Phenotype Gentotype Green seeds yy Yellow seeds (homozygous) YY Yellow seeds (heterozygous) Yy In pea plants round seeds (R) are dominant to wrinkled (r). Indicate the phenotype by typing either round or wrinkled in each blank below. Genotype Phenotype RR round Rr round rr wrinkled Punnett Square Practice. Fill in the Punnett Squares below, then answer the questions that follow. Pay attention to capitalization: uppercase means dominant; lowercase, recessive. Whenever you write a heterozygous genotype in a particular box in Punnett Square, remember to write the uppercase letter first, then the lowercase letter (example: Pp, not pP). In pea plants, tall height (T) is dominant to short height (t). Two heterozygous tall plants are crossed. Height(T = tall, t = short) T t T TT Tt t Tt tt What is the percent chance that the offspring will be tall? 0% 25% 50% 75% 100% Punnett Square Practice Assume that brown eyes (R) is dominant to blue (r). One parent is heterozygous for brown eyes while the other is homozygous for blue. Complete the cross and find the offspring. Eye Color (R = brown, r = blue) R r r Rr rr r Rr rr What is the percent chance that the offspring will have blue eyes? 0% 25% 50% 75% 100%