BI SC 004 Lecture Notes - Lecture 4: Cell Membrane, Cell Division, Cell Theory
Document Summary
A cell is the basic unit of life: bacteria, human. All living things are made up of cells. New cells arise from pre-existing cells: can"t spontaneously get cells. Different cell types define the 3 domains of life on earth. Bacteria, archaea and eukarya are classified based on unique features of cell structure and biochemistry. The 2 major types of cells in all living organisms. Prokaryotic cells: thought to be the first cells to evolve, lack a nucleus, represented by bacteria and archaea. Eukaryotic cells: have a nucleus that houses dna, many membrane-bound organelles. A plasma membrane that surrounds the cell. A cytoplasm: the semi-fluid substance inside the cell that contains organelles. Both contain dna as their genetic material. It is embedded with proteins: usually an important function. It contains cholesterol for support: cholesterol is not always bad, essential for structure for your cells. Too much cholesterol is not good for your body.
