Identify the INCORRECT statement about the endocrine system: MCQ with Answer and Explanation

Explanation:
RNA contains uracil instead of thymine found in DNA. In DNA, adenine pairs with thymine; in RNA, adenine pairs with uracil. Adenine, guanine, and cytosine are common to both. Uracil is a pyrimidine base, structurally similar to thymine but lacking a methyl group. This distinction is used in genetic material identification and understanding transcription.

Explanation:
Crossbreeding involves mating individuals of different breeds to combine desirable traits and exploit hybrid vigor (heterosis). Inbreeding is within the same breed, outcrossing is within breed but unrelated, grading up is repeated crossing with a superior breed. Crossbreeding improves productivity in dairy and meat animals.

Explanation:
Crystallization is a property of non-living substances where molecules arrange in a definite pattern, e.g., salt crystals. Living organisms exhibit growth, reproduction, metabolism, cellular organization, and consciousness. Metabolism is a defining feature of all living organisms, occurring even in unicellular forms. Reproduction, though absent in sterile organisms like mules, is generally a characteristic. Growth in living beings is internal and intrinsic, unlike extrinsic accumulation in non-living things. Hence, crystallization is not a characteristic of life.