Essay Database

cells= the basic units of living organisms Van Leeuwenhoek= used the simple light microscope (one lens, used natural light) compound light microscope (200 years later)= uses a series of lenses to magnify objects in steps, magnifies up to 1500 times. (what we use today) Robert Hooke= designed the early compound microscope (1655); looked at cork; he saw little shapes which looked like cells in a jail (monastery), he called them "cells". Matthias Schleiden= all plants are composed of …

…cell 2. the cell is the basic unit of organization of organisms 3. all cells come from pre-existing cells electron microscope= uses a beam of electrons rather than light; can magnify 500,000 times. used to see structures inside of a cell Two Types of Cells: 1. prokaryotes: cells that lack internal membrane-bound structures 2. eukaryotes: cells that have internal membrane-bound structures; most plant and animal cells organelles= membrane-bound structures within a cell; "little organs" nucleus= central organelle; manages cellular functions