Cells are the basic unit of all living things. All organs are made up of one or more cells. Cells are produced from other cells. All three of these statements come from the cell theory. The cell theory is a theory that is widely accepted as a truth.
All cell are alive and carry out respiration, reproduction (meiosis) and growth (mitosis). Cells arise from stem cells and become specialized for distinct functions such as; contraction, conduction, secretion, absorption, and protection. Cell specialization is also known as cell differentiation. All cells have a few things in common. For example: Cell membrane, DNA, cytoplasm, and ribosomes. Cell shapes vary greatly. They include spheres, cubes, flat, column, and doughnut shaped cells. Some cells are long and narrow, such as neurons. Other cells are wide and short like erythrocytes. Some cells are enclosed in a rigid cell wall, while others have a flexible cell membrane or none at all.
As you will read on through this site you will find out even more interesting facts about cells and cell processes.
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