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1. Sunflowers with small flowers measuring 10 cm in diameter are crossed with plants that have large flowers with a diameter of 16cm. All offspring in the F1 generation have medium size flowers with 13 cm in diameter. When crossing two F1 generation flowers, the F2 generation shows 4 flowers are 10 cm in diameter and 4 are 16 cm in diameter. Between these are 5 phenotypic classes with diameters intermediate to those at the extremes. a) Assuming that the alleles that contribute to flower diameter act additively, how many genes control flower size? b) How much does each additive allele contribute to flower diameter? c) What size flower makes up the largest phenotypic class?

1. The height of a wheat plant is determined by several genes. In a variety the minimum size is 12 inches and the maximum is 24 inches. 12-inch plants were crossed with 18-inch plants, and produced an 18-inch F1. The F1 was allowed to cross each other, and an F2 was obtained in which the 12 and 24 inch plants were obtained with a frequency of 2/8195. How many genes are involved in determining plant size in this variety of wheat? Select one: a. 5b. 6c. 4d. 3

1. The petals of the blue-eyed Mary (Collinsia parviflora) are normally blue. There are color variants of white and pink. Two pure breeding lines, one with pink petals and another with white petals were collected and the following crosses were made, with results shown in the table below: parents F1 F2 blue x white blue 101 blue, 33 white blue x pink blue 192 blue, 63 pink pink x white blue 272 blue, 121 white, 89 pink A. Define the allele symbols that can be used and show the genotype of parents, F1 and F2.  B.  A cross between a certain blue F2 plant and a certain white F2 plant gave progeny of which 3/8 were blue, 1/8 were pink, and ½ were white. What must the genotypes of these two F2 plants have been?

2. Three different pure-breeding strains of corn that produce ears with white kernels were crossed to eachother. In each case, the F1 plants were all red, whileboth red and white kernels were observed in the F2generation in a 9:7 ratio. These results are summarized in the following table.F1 F2white-1 × white-2 red 9 red : 7 whitewhite-1 × white-3 red 9 red : 7 whitewhite-2 × white-3 red 9 red : 7 whitea. How many genes are involved in determiningkernel color in these three strains?b. Define your symbols and show the genotypes for thepure-breeding strains white-1, white-2, and white-3.c. Diagram the cross between white-1 and white-2,showing the genotypes and phenotypes of the F1and F2 progeny. Explain the observed 9:7 ratio.

D D 1 2 d In a particular plant, leaf color is controlled by gene locus D. Plants with at least one allele D have dark green leaves, and plants with the homozygous recessive dd genotype have light green leaves. A true-breeding, dark-leaved plant is crossed with a light-leaved one, and the F1 offspring is allowed to self-pollinate. The predicted outcome of the F2 is diagrammed in the Punnett square shown in the figure, where 1, 2, 3, and 4 represent the genotypes corresponding to each box within the square. Which of the boxes marked 1-4 correspond to plants with a heterozygous genotype? O 1 only O 1, 2, and 3 2 and 3 2, 3, and 4 4) 3.

1. P is a dominant allele for purple flowers and p is the recessive allele that causes white flowers. The following cross is performed: Pp x pp. What percentage of offspring would you expect to have white flowers? 2. In peas, T (tall) is dominant to t (dwarf). A homozygous dominant plant is crossed to a heterozygous plant. What is the expected outcome for the genotype ratio of offspring from this cross? What percentage of offspring would you expect to be tall? 3. In peas, Y (yellow seeds) is dominant to y (green seeds) and R (round seeds) is dominant to r (wrinkled seeds). The following cross is performed: YYRr x yyrr. What is the expected phenotype ratio of the offspring?

1. Use the following information to answer the question: Parental cross is RrYy x RrYy                                                                                                       Seed Shapes are R-round, r-wrinkled                                                                                                       Seed colors are Y-yellow, y-green   Based on the information given, what is the phenotype ratio of the offspring of this cross? 2. A pea plant heterozygous for height and seed color (TtYy) is crossed with a pea plant heterozygous for height but homozygous recessive for seed color (Ttyy). If 80 offspring are produced, how many are expected to be tall and have yellow seeds?  3. What is the chromosome theory of inheritance? How does this theory explain Mendel's results? 4. A cross between two organisms heterozygous for two different genes (AaBb) results in a 9:3:3:1 phenotype ratio among the offspring. Is the offspring's genotype ratio the same? Explain your answer.…

1. Complete the Punnett square for a cross between a homozygous red-flowered snapdragon (RR) and a homozygous white-flowered snapdragon (WW). Give the ratio for the phenotype and the genotype. Key F1 Genotypic Ratio: RR – red Phenotypic Ratio: wW- white RW- pink 2. Complete the Punnett Square for a cross between two Fi plants (WW). Give the phenotypic ratio for the F2 generation. F2 Phenotypic ratio: 3. Cite some possible applications of genetics to plant breeding.

Sunflowers with small flowers measuring 10 cm in diameter are crossed with plants that have large flowers with a diameter of 16cm. All offspring in the F1 generation have medium size flowers with 13 cm in diameter. When crossing two F1 generation flowers, the F2 generation shows 4 flowers are 10 cm in diameter and 4 are 16 cm in diameter. Between these are 5 phenotypic classes with diameters intermediate to those at the extremes. What size flower makes up the most common phenotypic class?

3.) A Heterozygous tall heterozygous red flowered plant is crossed with a Homozygous short white flowered plant. What is the genotype of the heterozygous tall heterozygous red flowered plant? What is the genotype of the homozygous short white flowered plant? Fill in the genotype in the parentheses and FOIL each parent’s genotypes: heterozygous tall heterozygous red flowered plant ( homozygous short white flowered plant ( How many of the 16 offspring are: tall & red tall & white short & red short & white

4. In pea plants, tall (T) plants are dominant to short (t), and green pods (G) are dominant to yellow (g). Perform a Punnett square analysis for the following crosses, with the parental gametes and all possible offspring genotypes that could be produced. **Include the phenotypic ratios for the offspring. (a) TtGG × TTgg

*Genes A and B are linked. Individual plants homozygous for different combinations of these genes (AABB, aabb, AAbb, aaBB) were crossed at random to produce Fi plants. The F₁ plants were self pollinated to produce the F2. The F₂2 progeny from six of the F₁ self pollinations are listed below. F₁ Plant 1 2 3 4 S 2. Number of F₂ plants in each phenotypic class AB Ab aB 98 10 34 3. 64 106 50 99 25 8 104 23 31 a. Determine the genotype of the F₁ that produced each F2 population. 1. ab 32 18 MacBook Pro 36 2 5. 6. b. Calculate the recombination frequency between genes A and B. 100 Linkage Problem Set 13. Assume that height and eye color are inherited as follows. T- tall, t- short and B- blue, b- brown. Genes T and B are linked on chromosome 1, 20 map units apart. A tall brown eyed woman marries a short blue eyed man. They have a son that is tall and blue eyed. This man marries a short brown eyed woman. a. Diagram the arrangement of the alleles on the two chromosome 1's of the tall blue eyed…

7. In pea plants, inflated pod is governed by a completely dominant gene and a constricted pod by a recessive gene. Another independently segregating dominant gene produces green pod while recessive gene produces yellow pod. Give the genotypes of the parents in each of the crosses given below. Phenotypes of Offspring Inflated yellow Constricted yellow Parental Phenotypes Parental genotypes Inflated groen Constricted Green 7.1. inflated green x inflated yellow 58 62 18 22 7.2. constricted green x constricted green 56 18 7.3 inflated yellow x inflated yellow 64 20 74. inflated gr green x 36 38 inflated yellow 7.5. inflated green x inflated green 178 62 58 22

7. In pea plants, inflated pod is governed by a completely dominant gene and a constricted pod by a recessive gene. Another independently segregating dominant gene produces green pod while recessive gene produces yellow pod. Give the genotypes of the parents in each of the crosses given below. Phenotypes of Offspring Parental Phenotypes Parental genotypes Inflated Inflated Constricted Constricted yellow green yellow Green inflated green x inflated yellow 7.1. 58 62 18 22 7.2. constricted green x 56 18 constricted green 7.3 inflated yellow x 64 20 inflated yellow inflated green x inflated yellow 7.4. 36 38 inflated green x inflated green 7.5. 178 62 58 22

2. Figure 8.10 In pea plants, round seed shape (R) is dominant to wrinkled seed shape (r) and yellow peas (Y) are dominant to green peas (y). What are the possible genotypes and phenotypes for a cross between RrYY and rrYy pea plants? How many squares do you need to do a Punnett square analysis of this cross?

4). In papayas, sour fruit (S) is dominant over sweet fruit (s), and green skin (G) is dominant over yellow skin (g). The genes for these characteristics independently assort. A homozygous plant with sour fruit and green skin is crossed with a homozygous plant with sweet fruit and yellow skin. Two individuals from the F1 generation are then crossed to produce an F2 generation.

If a heterozygous F1 Tobacco plant was crossed to an albino plant, what is the expected number of green and white plants in the next generation? (show Punnett square)  A woman homozygous dominant for albinism marries a man who is homozygous recessive for albinism. What are the possible genotypes and phenotypes percentages for their offspring? A man that can roll his tongue is heterozygous for the trait marries a woman that cannot roll her tongue. They have a child. The rolling tongue is dominant to not rolling tongue. What is the man’s genotype for tongue rolling? The women? Show the Punnett square for the child’s genotype Give the probability (percent chance) that the child can or cannot roll their tongue. Oh no! The F1 and F2 generation seed packet labels were mixed around. How would we know which seeds we planted by observing the color of the leaves? (Hint: What are the genotypes of the two generations? What color leaves do they produce in what ratios?)

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x² R AA E Paragraph 255 129 112 1 heavy, green, long heavy, green, ovate heavy, yellow, ovate heavy, yellow, long light, yellow, oblate V light, yellow, long light, green, long light, green, ovate Normal No Spacing In an East Indian mango, three genes are linked on the same chromosome. Heavy bloom is dominant to light bloom, skin that is green is dominant to skin that is yellow, and fruit with a long shape is dominant to ovate shape. A plant that is true-breeding for the dominant traits was crossed to a light, yellow and ovate fruit. The F1 plants were then testcrossed to light, yellow and ovate fruit. The following results were obtained: 251 111 133 21 Styles Heac a) Diagram the crosses for the parental generation and F1 test cross. b) Construct a genetic map that shows the order of these three genes and the distances between them.

In corn, a colored aleurone is due to the presence of an R allele; r/r is colorless. Another gene controls the color of the plant, with g/g being yellow and G_being green. A plant of unknown genotype is test-crossed, and the following progeny plants were obtained. Colored green 89 Colored yellow 13 Colorless green 9 Colorless yellow 92 What was the phenotype and genotype of the plant used for the test cross?   A. Colorless green - rG/rg   B. Colorless yellow - rg/rg   C. Colored yellow - Rg/rg   D. Colored green - RG/rg

8. Kernel color in wheat is controlled by 2 pairs of genes (AABB). Determine the color of the offspring with the following genotypes: (Note: 4 contributing alleles – red; 3 contributing alleles – medium red; 2 contributing alleles – intermediate red; 1 contributing allele – red; and 0 – white AAbb x AaBb AABb x Aabb aaBb x Aabb AABb x aabb AABb x AaBb   A wheat plant producing medium red seed is crossed with another plant producing intermediate red seed (refer to problem no. 8). How many individuals will be? Red Medium red Intermediate red Light red White

In pineapples, leaves may be spiny, spiny-tipped or piping. Pineapples of different phenotypes were used in the following crosses: Pl phenotype piping X spiny P1 genotype Fl phenotype 100% piping F1 genotype Crossing the Fls produced: F2 phenotypes F2 genotypes ww gm 95 piping 25 spiny tipped 8 spiny Using the letters A and B, give the COMPLETE genotypes of ALL the individuals. SOLUTION Get the total of the F2 generation

In garden pea, resistance to a certain disease is controlled by a single locus with dominance forresistance (R) and recessive susceptible (r). Another locus governs seed color with yellow being dominant (Y)to green (y). A pea plant which is heterozygous for both gene pairs is crossed with a susceptible and green-seeded plant. The following data was observed in the progeny. Phenotype                                NumberResistant yellow                           43Susceptible green                         49Resistant green                             16Susceptible yellow                         12Total                                               120 a. What is the calculated chi-square value based on an independent assortment assumption? Compute forthe df and write the conclusion. (NOTE: The cross will not yield a 9:3:3:1 ratio since not both of theparental genotypes are heterozygous for the 2 pairs of alleles. Thus, perform the cross first, show theparental genotypes, the gamete…

9. In the F2 Generation, both the male and female pea plants are heterozygous for round/wrinkles seeds. 1)Draw a Punnett square that shows this cross. 2)What are the possible genotypes? 3)What are the possible phenotypes? 10. In pea plants, the allele for smooth pods (P) is dominant over the allele for pinched pods (p). Construct a Punnett Square that shows a cross between an PP plant and an Pp plant. Predict what percent of the offspring are likely to have smooth pods. Essay: Is it possible for a son to inherit an allele on an X chromosome from his father? Explain why or why not.