Une journée scientifique autour des motifs et des cycles algébriques .
In this talk I will review Chow groups and étale motivic cohomology groups of smooth complete intersections with Hodge structures of level one, classified by Deligne and Rapoport, with particular attention to fivefolds. We will see how these results extend to algebraic cycles on other smooth Fano manifolds with Hodge structures of level one and, as an application, we prove the integral Hodge conjecture for smooth quartic double fivefolds by means of the étale motivic approach. This is based on a joint work with Pedro Montero.