HISTORY OF CELLS
The development and refinement of magnifying lenses and light microscopes made the observation and description of microscopic organism and living things possible. Continued advances in microscopy allowed observation of cell organelles and ultra-structure.
The development and refinement of magnifying lenses and light microscopes made the observation and description of microscopic organism and living things possible. Continued advances in microscopy allowed observation of cell organelles and ultra-structure.
Cell Theory
- Living things are composed of one or more cells .
- Cells come from preexisting cells through cell reproduction.
- Cells are the basic unit of structure and function in all living things.
- Cells contain specialized structures to perform functions necessary for life.
- Energy flow (metabolism and biochemistry) occurs within cells
- Cells contain hereditary information (DNA) that is passed from cell to cell during cell division.
- All cells are basically the same in chemical composition in organisms of similar species.
Cell Scientists
- Leeuwenhoek saw microscopic organisms in pond water.
- Schwann discovered "all animals are made of cells".
- Schleiden discovered "all plants are made of cells".
- R. Hooke coined the term "cells" when looking at cork from trees.
- R. Virchow discovered that all cells come from preexisting cells.
Cell Organization
- The basic processes necessary for living things to survive are the same for single cells are they are for a more complex organism.
- A single-celled organism has to conduct all life processes by itself.
- A multicellular organism has groups of cells that specialize to perform specific functions. These cells form tissues. The tissues form organs. The organs form organ systems. The organ systems work together to keep the organism alive.