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A man with pure blue eyes and pure black...

A man with pure blue eyes and pure black hair marries a woman with black eyes and red hair. (black eyes are dominant over blue eyes and black hair over red hair). What will be the probabilities of phenotypes of the children?

A

50% with black eyes and black hair, and 50% blue eyes and black hair

B

All will be with black eyes and black hair

C

Both the bove cases are possible

D

`1:1:1:1`

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AI Generated Solution

The correct Answer is:
To solve the problem of determining the probabilities of phenotypes of the children from a man with pure blue eyes and pure black hair and a woman with black eyes and red hair, we will follow these steps: ### Step 1: Determine the Genotypes of the Parents - The man has **pure blue eyes** and **pure black hair**. - Blue eyes are recessive, represented as **bb** (homozygous recessive). - Black hair is dominant, represented as **HH** (homozygous dominant). - Therefore, the man's genotype is **bbHH**. - The woman has **black eyes** and **red hair**. - Black eyes are dominant, represented as **B_** (can be either homozygous dominant **BB** or heterozygous **Bb**). - Red hair is recessive, represented as **hh** (homozygous recessive). - Therefore, the woman's genotype can be either **BBhh** or **Bbhh**. For this problem, we will consider both cases. ### Step 2: Determine the Possible Gametes - The man can produce gametes with the following combinations: - From **bbHH**, the only gamete produced will be **bH**. - For the woman, we will consider both possible genotypes: 1. If the woman is **BBhh**, she can only produce **Bh** gametes. 2. If the woman is **Bbhh**, she can produce **Bh** and **bh** gametes. ### Step 3: Perform the Punnett Square Analysis #### Case 1: Woman is **BBhh** - Cross the gametes: - Man: **bH** - Woman: **Bh** | | Bh | |---------|-------| | **bH** | BbHh | - Offspring Genotype: **BbHh** (Black eyes, Black hair) #### Case 2: Woman is **Bbhh** - Cross the gametes: - Man: **bH** - Woman: **Bh** and **bh** | | Bh | bh | |---------|-------|-------| | **bH** | BbHh | bbhh | - Offspring Genotypes: - **BbHh** (Black eyes, Black hair) - **bbhh** (Blue eyes, Red hair) ### Step 4: Determine the Phenotypic Ratios - **Case 1 (Woman BBhh)**: - 100% of children will have **Black eyes and Black hair**. - **Case 2 (Woman Bbhh)**: - 50% will have **Black eyes and Black hair** (BbHh). - 50% will have **Blue eyes and Red hair** (bbhh). ### Final Probabilities of Phenotypes - If the woman is **BBhh**: 100% Black eyes and Black hair. - If the woman is **Bbhh**: - 50% Black eyes and Black hair. - 50% Blue eyes and Red hair. ### Summary The probabilities of phenotypes of the children depend on the genotype of the mother: - If the mother is **BBhh**: 100% Black eyes and Black hair. - If the mother is **Bbhh**: 50% Black eyes and Black hair, 50% Blue eyes and Red hair.

To solve the problem of determining the probabilities of phenotypes of the children from a man with pure blue eyes and pure black hair and a woman with black eyes and red hair, we will follow these steps: ### Step 1: Determine the Genotypes of the Parents - The man has **pure blue eyes** and **pure black hair**. - Blue eyes are recessive, represented as **bb** (homozygous recessive). - Black hair is dominant, represented as **HH** (homozygous dominant). - Therefore, the man's genotype is **bbHH**. ...
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