Question

Where are sperm created? Where are they stored?

Answer 1

Sperm is the male reproductive cell, commonly called gamete, found in anisogamous forms of sexual reproduction. Animals produce motile sperm with a tail (flagellum), called spermatozoa. Some red algae and fungi produce non-motile sperm cells, called spermatia. Flowering plants contain non-motile sperm inside its pollen, while some basal plants like ferns and certain gymnosperms have motile sperm.

Complete answer:
Sperm cells are formed during the process called spermatogenesis. In amniotes, i.e., reptiles and mammals, the production of sperms occurs in the seminiferous tubules of the testes. Spermatogonia differentiates into spermatocytes which undergo meiosis, reducing their chromosome number by half. The end result is spermatids which then mature into motile sperm cells. In animals, spermatids construct a tail, or flagellum. The whole process occurs constantly and takes around 3 months from start to finish. The process starts with the production of spermatogonia from germ cell precursors. Sperm cells in algal and several plant gametophytes are produced in the male gametangia (antheridia) via a process called mitotic division. In flowering plants, sperm nuclei are produced inside the pollen.
In mammals, sperms are stored in the epididymis. It is released from the penis during ejaculation in a fluid known as semen. Epididymis is a highly convoluted duct behind the testis, along which the sperm passes towards the vas deferens.

Note:
A germ cell is any biological cell that gives rise to the gametes of a sexually reproducing organism. In many animals, the germ cells originate in the primitive streak. They migrate via the gut of an embryo to its developing gonads and eventually undergo meiosis to generate sperms.