Separately, they do not constitute a human.
Again, it is your concept of 'human' that seems to be trapped in limited view. "A" human? While it's understandable, it is an over simplified view that we are each islands unto ourselves. It is a very anthropocentric view.
A look at various other forms of life and reproduction may help. Corals and jellyfish, for instance, have two life forms. The polyp which is a sessile clone type. (The predominant life form in corals) and a free living form (the predominant form in jellyfish). But both species have both forms. In corals, the free living form, which looks just like a jellyfish, is microscopic. It is part of what is called plankton. They float around the oceans and have sex. The fertilized eggs hatch into large and attach to a solid serface and grow into asexual organisms (what we see as coral) that grow more like plants, budding and growing and making exact copies of themselves, they form huge colonies of beautiful corals. At some point the polyps bud new madusa, which are male and female, invisible to our eye.
By your view you'd have to say that the coral reefs are in fact NOT CORALs because they are not fertilized, they are nothing more than unfertilized, 1N, asexual organisms, and do not become coral unless they are somehow joined with another and become 2N, sexual, invisible, organisms, of which 99.99999% will die without ever reproducing.
Your view that the sexual form is THE HUMAN is entirely anthropocentric. It appears to be that way, not because it IS that way in universal terms, but because it is that way by particular, historical, anthropocentric accident. During the millions and millions of years of evolution, many reproductive strategies have arisen. The strategy of separating and recombining sets of genetic material is amazing. But your view that only the combined entity constitutes the species while the uncombined entity is meaningless is ill informed. Literally 1000s of examples of species can easily prove that the uncombined entity certainly can be as viable and even more dominant the combined form.
In humans, the uncombined form is like a mosquito; literally millions them have to be produced so that one may survive to the next stage.