Plant reproductive morphology is asexual, producing only spores. Similarly, flowers produced by the sporophyte may be described as "unisexual" or "bisexual", meaning that they give rise to either one sex of gametophyte or both sexes of gametophyte. The flower is the characteristic structure concerned with sexual reproduction in flowering plants (angiosperms). Flowers vary enormously in their construction (morphology). A "complete" flower, like that of "Ranunculus glaberrimus" shown in the figure, has a calyx of outer sepals and a corolla of inner petals. The sepals and petals together form the perianth. Next inwards there are numerous stamens, which produce pollen grains, each containing a
Surround channels strictly diffuse. Optimally there should be discrete surround channels for diffuse and direct effects. This is part of the design for Tomlinson Holman's 10.2 surround sound. For movies surround channel information is usually more diffuse ambient noise. Some surround sound systems such as Dolby Digital EX and Pro Logic IIx incorporate a third (back surround) or even fourth surround channel (back left and back right). These channels are "matrixed" from the standard surround channels; they are not discrete. Some matrix encoding surround sound systems use a single back center channel surround (Dolby Digital EX, Dolby Pro Logic IIx 6.1) or