Understanding Cells

Microscopes Light Microscope- Uses light and lenses to magnify the image of an object Compound Microscope- A light microscope that uses more than one lens to magnify an object Electron Microscope- Magnetic field to focus a beam of electrons through an object. Most complex type of microscope.

Microscopes

Electron microscope photos

Cell Theory As scientists developed new microscopes they began to study cells. Ruldolf Virchow, Theodor Schwann and Matthias Schleiden all developed the cell theory. The cell theory states: all living things are made up of one or more cells, the cell is the smallest unit of life and cells com from preexisting cells.

Basic Cell Substances Many parts of a cell are made of smaller parts linked together. These parts are called macromolecules. Water is the main ingredient in all cells. 70% of a cells volume is water. The structure of a water molecule is essential for the dissolving of nutrients into cells.

Types of Macromolecules Nucleic Acids- Long chains of nucleotides join together to make DNA and RNA Proteins- Long chains of amino acid molecules. They contain instructions on how to join acids together Lipids- Large molecules that do not dissolve in water. They are protective barriers in cells. (Ex: Cholesterol) Carbohydrates- Sugar molecules can store energy, provide support and are needed for communication.

DNA vs RNA