Albinism is due to nonsynthesis (absence) of melanin on account of absence of

Options

A. Melanase
B. luciferase
C. tyrosinase
D. lysine

Answer

### Step-by-Step Solution:

1. **Understanding Albinism**: Albinism is a genetic condition characterized by the absence of melanin, which is the pigment responsible for the color of skin, hair, and eyes.

2. **Role of Melanin**: Melanin is produced by specialized cells called melanocytes. The production of melanin is regulated by various factors, including hormones.

3. **Hormonal Regulation**: The hormone responsible for stimulating the production of melanin is called Melanocyte Stimulating Hormone (MSH). This hormone is secreted by the pituitary gland.

4. **Chemical Nature of Melanin**: Melanin is synthesized from the amino acid tyrosine. The enzyme that catalyzes the conversion of tyrosine into melanin is known as tyrosinase.

5. **Identifying the Absence**: In individuals with albinism, there is a deficiency or absence of the enzyme tyrosinase, which leads to the non-synthesis or absence of melanin.

6. **Conclusion**: Therefore, the absence of melanin in albinism is due to the absence of the enzyme **tyrosinase**.

### Final Answer:
Albinism is due to the absence of **tyrosinase**.

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