I understand, and perhaps I misunderstand, that the sperm of the rooster is stored in the hens body until a egg passes by and then it is fertilized? So does a rooster deposit sperm that effects several eggs, or must he make a fresh deposit for each egg?
A mature ovary, which looks like a cluster of grapes, may contain up to 4, small ova. Each of these ova can develop into a yolk. On each yolk is a white spot called the germinal disc, this is the true ova.
All eggs, whether fertile or not contain this disc. Crack an egg open and see if you can find it. The rooster covers the hen and holds onto the feathers on the back of her head with his beak while steadying himself on top of her with his feet.
She sort of stoops to present herself to him and to endure his weight. It is a dual purpose organ for the purpose of mating as well as excrement.
Often times the cloaca is referred to as the vent.
When the cloaca are brought together, the sperm is transferred from the rooster to the hen. Once a rooster and hen mate, the sperm is held in the oviduct.