…of chromosomes and is called diploid. When one haploid gamete fuses with another haploid gamete during fertilization, the resulting combination, with two sets of chromosomes, is called a zygote. Either immediately or at some later time, a diploid cell directly or indirectly undergoes a special reductive cell-division process (meiosis). Diploid…

…are entirely dependent upon the diploid sporophyte plant. Gymnosperms and angiosperms form two kinds of spores: microspores, which give rise to male gametophytes, and megaspores, which produce female gametophytes.

…1n, or haplontic; 2n, or diplontic; and 1n-2n (2n-1n). The former two types have collectively been called haplobiontic or monobiontic, because the life histories include only one phase; the third type has been called haplodiplontic, diplohaplontic, diplobiontic, dibiontic, or sporic, because the life history involves two alternating multicellular phases, or…

… (sex cells) and is thus diploid (contains two sets of similar chromosomes). At maturity, the sporophyte produces haploid (containing a single set of chromosomes) spores, which grow into the gametophyte generation. At their sexual maturity, the gametophytes produce haploid gametes that unite to begin a new cycle.

In the sporophyte phase a diploid (having two sets of chromosomes) plant body grows and eventually produces spores through meiosis. These spores divide mitotically to produce haploid (having a single set of chromosomes) gamete-producing bodies called gametophytes. The union of two gametes during fertilization produces a diploid