Cell Structure and Function 7.1

The Discovery of the Cell Single cells are too small to see what the naked eye During the late 1600’s Robert Hooke was the first to create a microscope to cells inside a sample of cork Anton van Leeuwenhoek began to observe microscopic organisms using a compound microscope Cell Theory (PLEASE REMEMBER) All living things are made of cells Cells are the basic unit of life New cells are produced from existing cells

Exploring the Cell As technology has advanced we have created powerful microscopes Compound Light Microscope Nearly all cells are transparent – we use dyes and stains to add color Fluorescent (Glow in the Dark) markers Electron Microscopes Uses electrons (e-) to create a digital image Normally in black and white

So what has microscopes taught us? Cells come in a variety of shapes and sizes All cells have DNA All cells have a cell membrane aka plasma membrane PROKARYOTES DNA and ribosomes just float around the cell EUKARYOTES Membrane bound organelles and nucleus (DNA hangs out here) BACTERIA Cell membrane, cell wall and few other essentials PLANTS Cell wall, central vacuole & chloroplasts ANIMALS Jammed packed full of cool organelles

Quiz What is the main difference between prokaryote’s and eukaryote’s cells. Name two types of microscopes? Why do we ”stain” cell samples before viewing them?

Answer Prokaryotes are smaller, simpler organisms that do not have a membrane bound DNA or organelles. Light microscope and electron microscopes To help us see certain parts of the cell more clearly