Lis la définition suivante. Écris le mot qui est décrit par…

Lis la définition suivante. Écris le mot qui est décrit par cette définition. (Le mot/expression doit faire partie de la liste étudiée). Ensemble des phénomènes matériels et idéologiques qui caractérisent un groupe ethnique ou une nation, une civilisation, par opposition à un autre groupe ou à une autre nation (Larousse).    

Worldwide, only about 35% of adults can digest lactose, the…

Worldwide, only about 35% of adults can digest lactose, the primary sugar in milk. Breakdown of lactose requires the enzyme lactase; while it is normal for all mammals to express lactase as an infant, in most species, including humans, the gene is turned off at weaning.  Thus, in most people, consumption of dairy products in adulthood is less than pleasant, a condition termed lactose intolerance.  Lactose intolerance is caused by the non-persistence of lactase expression.  The mutation that led to lactase-persistence (continued expression of lactase) is thought to have risen in frequency in pastoralist populations – those that started domesticating and farming animals.  Lactase persistence (LP) arose independently in both African and European populations.  The African and European populations have different LP mutations, but all LP mutations are in the regulatory region of the lactase gene. . Thus, lactase persistence demonstrates:

Remember hilltopperitis = all those affected have blue hair…

Remember hilltopperitis = all those affected have blue hair and yellow skin, about 50% of those affected have tiny horns, and the others have very noticeable horns.  You are interested in finding the gene(s) responsible for the horn phenotype; you decide to approach this by using a microarray. You isolate mRNA from tiny horns and large horns. You use the mRNA to create fluorescently labeled cDNA –  blue (tiny) and yellow (large) (blue+yellow = brownish-grey).  You use these samples to probe a human microarray that contains sequences representing ALL human protein coding genes. Explain the rationale for using samples from individuals with tiny horns and large horns.  How will these samples be useful for identifying genes involved in this phenotype? (In other words, if a gene is responsible for the horn phenotype, how will it’s expression be different in individuals with tiny horns and large horns?)