Note: There is currently no formal definition of Intelligenceplugin-autotooltip__plain plugin-autotooltip_bigIntelligence
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"Numerous definitions of and hypotheses about intelligence have been proposed since before the twentieth century, with no consensus reached by scholars."
Source wikipedia"
Despite the lack of an agreed definition, tests of IQ (Intelligence Quotients) are still routinely used to grade students, job-applicants and patients.
Theories regarding the inheritance of human intelligence are highly controversial, nevertheless, it's widely believed that various aspects of intelligence can, to some extent, be inherited.
Recent studies suggest that genes related to intelligence are predominantly located on the X chromosome. With the implication that a significant proportion of intelligence is passed on to male offspring from the maternal side, and to the female offspring from either (or both) the maternal and paternal side.
There is no explanation as to why the X chromosome seems to carry more intelligence-related genes. There is also no agreement on how significant genetic factors might be.
Further info. X-linked genes and mental functioning Human Molecular Genetics, Volume 14, Issue supplement_1, 15 April 2005, Pages R27–R32