The cell wall surrounds the cell membrane in plant cells, bacteria, and some fungi. In plant cells, the cell wall is composed of cellulose. In bacteria, the wall is made mostly of polypeptides (protein) or polysaccharides (carbohydrates). The cell wall provides support and protection and is responsible for giving plant cells their shape. Another important structure found only in eukaryotic cells is the nucleus . This struc-ture contains the genetic information and is the control center of the cell. Protecting the nucleus is a double-membrane called the nuclear envelope , which, like the plasma membrane, is semi-permeable.
Welcome to the Bisha Mining Share Company. Bisha Mining is an Eritrean company formed for the development and operation of the Bisha Mine in western Eritrea. It is owned by Nevsun Resources Ltd. (60%) and the Eritrean National Mining Corporation (ENAMCO) (40%). The Bisha Mine is a high-grade copper, gold, silver and zinc mine that commenced production in February 2011.
Wealth Minerals is an Emerging Lithium Company. 1  Wealth Minerals Ltd is a junior mineral resource exploration company. It engages in the acquisition, exploration, and development of mineral properties primarily in Latin America and British Columbia. Most recently, they have orchestrated the acquisition of key lithium salars in Chile, the home of some of the worldâs largest lithium companies.