All living things are made of cells, the smallest unit that can carry on all the processes of life

In 1665, Robert Hooke observed the first cells from thin slices of cork. He gave them the name "cells" because they reminded him of small rooms or cells that monks lived in.

In 1675, Anton van Leeuwenhoek was the first person to observe living cells. He looked at protozoans from pond water.

CELL THEORY About 150 years later scientists organized their observations into a cell theory: - All living things are composed of one or more cells. - Cells are the basic units of structure and function in an organism. - Cells come only from existing cells.

Prokaryotic Cells (Bacteria) The average size is about 1 micrometer. Bacteria have no nucleus and no membrane-bound organelles. An organelle is a cell component that performs specific functions for the cell.

Cell Membrane - separates the cell from its environment. It regulates what moves into and out of the cell. The Fluid Mosaic Model: the cell membrane is made up of 2 layers of phospholipids with proteins embedded throughout. These lipids and proteins constantly move laterally creating a fluid motion.

Cytoplasm the entire contents of the cell, except the DNA.

Ribosomes site where proteins are made.

Nucleoid tangled ball of DNA; tells cell what proteins to make. It is not called a nucleus because the DNA is not contained within a membrane.

Plasmids small rings of DNA (separate from the nucleoid).

Pili (pilus) appendages that allow the bacteria to adhere to other surfaces.

Flagella long extensions that aid in movement

Cell Wall outer rigid layer; maintains the shape of the cell and adds protection.