Â­Mesoamericans began writing during the mid-Pre-classic period. The Mayans were the first to keep any sort of historical record, and the beginnings of the calendar were born. The Mayans used stelae, or stone monuments, to carve their civil events, calendars and astronomy knowledge. They also inscribed their religious beliefs and mythology on pottery.
The nucleus is a membrane bound structure that contains the cell's hereditary information and controls the cell's growth and reproduction. It is commonly the most prominent organelle in the cell. The nucleus is surrounded by a structure called the nuclear envelope.
Animal cells and plant cells both contain: cell membrane, cytoplasm, nucleus. Plant cells also contain these parts, not found in animal cells: chloroplasts, vacuole, cell wall. The table summarises the functions of these parts.lant and animal cells. Cytoplasm. Jelly-like substance, where chemical reactions happen. In plant cells there's a thin lining, whereas in animal cells most of the cell is cytoplasm. Plant and animal cells. Nucleus. Controls what happens inside the cell.