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Natural selection uses duplicated genes as raw material for functional innovation, co-opting their existing features to new functions. Understanding genetic innovation requires two questions to be ...

Females are more immunoreactive than males and, although sex hormones have an important role in immune functions, the X chromosome is fundamental in shaping sex-specific immune responses. X-linked ...

Enzymes help with specific functions that are vital to the operation and overall health of the human body. They help speed up chemical reactions and are essential for respiration, digestion, muscle ...