With the help of a schematic diagram describe the haplo-diptontic life cycle pattern in plants

In a sexually reproducing plant, there is an alternation of generation between a haploid and a diploid phase of plant bodies.
The haploid plant body is termed gametophyte while the diploid plant body is called sporophyte.
The gametophyte produces gametes by mitosis while the haploid spores are produced by sporophyte following meiosis (reduction division). Two gametes fuse together to produce a zygote which develops into the diploid sporophyte. In a haplodiplontic life cycle pattern, such as in bryophyta or pteridophyta both the phases of life are multicellular. 

However, in bryophytes, the gametophytes are small, photosynthetic, independent and represent dominant phase. The partly or totally dependent, the sporophyte is physically attached to the gametophyte. The (n) spores dispersed by sporophyte germinate into individual gametophytic plants. 

In pteridophytes, the 2n (diploid) phase is dominant, well organized, independent while the haploid phase though also free-living and independent is short lived and photosynthetic. 

In both of these groups of plants the mobile male gametes, antherozoid produced by sex organ antheridium, travel to archegonium (bearing an egg cell) via the medium of water. The egg cell is nonmotile. The reproduction is oogamous.