egrep (which is the same as grep -E) treats +, ?, |, (, and ) as meta-characters. In basic regular expressions (with grep), the meta-characters ?, +, {, |, (, and ) lose their special meaning. If you want grep to treat these characters as meta-characters, escape them \?, \+, \{, \|, \(, and \).
Plants, fungi, and some protists also perform meiosis. In plants, meiosis creates a multicellular haploid organism, called a gametophyte , which in some groups is independent of the diploid plant. Gametes are produced by mitosis of the gametophyte, which then fuse to form the embryo. This cycle is called alternation of generations. Meiosis involves two divisions.
Meiosis occurs only in sexually reproducing organisms. Depending on the organism, it may produce haploid gametes, which do not divide further but instead fuse to produce a diploid zygote; or it may produce haploid spores, which divide by mitotic cell cycles and produce unicellular or multicellular organisms. In animals, where the somatic (body) cells are diploid, the products of meiosis are the gametes. In many fungi and some algae, meiosis occurs immediately after two haploid cells fuse, and mitosis then produces a haploid multicellular adult organism (e.g., filamentous fungi, algae) or haploid unicellular organisms (e.g., yeast, unicellular algae).