Cobordisms between spheres

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In the category $Cob_n$ of closed $n-1$ dimensional manifolds and cobordisms between them, I am wondering what happens when we restrict our attention only to spheres. In the case when $n=2$, the only closed $1$ manifolds are disjoint unions of circles and any cobordism between any two closed $1$-manifolds can be built from pants, copants, cups and caps. Is it always true that any cobordism between two disjoint unions of spheres can be built from these elementary pieces?