Predicted Phenotypic Ratio of Offspring from Sam and Carole

Introduction

Black eyes are dominant to orange eyes, and green skin is dominant to white skin. Sam, a MendAlien with black eyes and green skin, has a parent with orange eyes and white skin. Carole is a MendAlien with orange eyes and white skin. If Sam and Carole were to mate, the predicted phenotypic ratio of their offspring would be determined.

Question

If Sam and Carole were to mate, the predicted phenotypic ratio of their offspring would be _____.

  1. 9 black eyes, green skin : 3 black eyes, white skin : 3 orange eyes, green skin : 1 orange eyes, white skin
  2. 1 black eyes, green skin : 1 black eyes, white skin : 1 orange eyes, green skin : 1 orange eyes, white skin
  3. 3 black eyes, green skin : 3 black eyes, white skin : 9 orange eyes, green skin : 1 orange eyes, white skin
  4. 1 black eyes, green skin : 3 black eyes, white skin : 3 orange eyes, green skin : 9 orange eyes, white skin
  5. There is insufficient information to determine Sam's genotype.

Answer

Final answer: 1 black eyes, green skin : 1 black eyes, white skin : 1 orange eyes, green skin : 1 orange eyes, white skin

By applying Mendelian genetics, the predicted offspring phenotype from Sam (BbGg) and Carole (bbgg) would be a 1:1:1:1 ratio for black eyes, green skin: black eyes, white skin: orange eyes, green skin: orange eyes, white skin.

Explanation: Given that black eyes are dominant to orange eyes, and green skin is dominant to white skin, we can use Mendelian Genetics to predict offspring traits. Sam, having black eyes and green skin, and a parent with orange eyes and white skin, must have heterozygous traits (carrying both dominant and recessive alleles: Bb for eye color and Gg for skin color). Carole, possessing recessive traits: orange eyes and white skin, has homozygous recessive traits (bb for eye color and gg for skin color).

When Sam and Carole mate, the predicted phenotypic ratio of their offspring would be 1 black eye, green skin: 1 black eye, white skin: 1 orange eye, green skin: 1 orange eye, white skin. This ratio comes from the combination of two independent monohybrid crosses: Bb x bb (for black vs orange eyes), and Gg x gg (for green vs white skin).

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