Early Scientists’ Contributions (The dead guys you need to know!) And... The Cell Theory

Remember Water??? We already learned about several of water’s unique properties Polarity Adhesion Cohesion Surface Tension Because of these properties, water “mounds-up” and is able to magnify whatever image is beneath it!

Let's Talk Microscopes... What does Magnify mean? - To increase the size What do you know about Microscopes? Do you know what a Compound Light Microscope is?

Simple Lenses

Anton van Leeuwonhoek Created the First Compound Microscope

Anton Van Leeuwenhoek A tradesman from Holland. Sold and Traded Drapery! First to discover Bacteria Considered the Father of Microbiology Microbiology means the study of small life He created the first compound microscope which allowed people to see “organisms” never before seen! He called them “animacules” An “organism” is a living thing!

Microscopes THEN

And Now…

Electron Microscopes Use electrons, not light, to view specimens Advantages Nanoscale imaging! (This means it can magnify the teeny-weeny stuff and show it on a computer screen for all to view!) Disadvantages Super expensive Specimens must be viewed in a vacuum… which means, specimens must be DEAD!

Electron Microscopes… A dust mite A spider

Pure Cane Sugar Maggot Ant Bed Bug Virus

10 award winning photos

Cork Cells Blood Cells

Robert Hooke Coined the term “cell” Viewed cork cells under the lens...

What IS a cell, anyway? A cell is the structural and functional unit of ALL organisms It is the smallest unit of life Often called the building block of life Each cell is actually ALIVE! Some organisms are unicellular What does THAT mean???? _________________ Some are multicellular

Schleiden & Schwann Schleiden and Schwann came up with the theory that all plant life (Schleiden) and animal life (Schwann) are composed of cells, that these cells were made from cells and that they end up making more cells...

Cell Theory The cell is the basic unit of structure & function of all living things. All living things (organisms) are made of cells. All cells come from pre-existing cells. Francesco Redi started this line of thought! Schleiden and Schwann helped it along... Life doesn’t just “appear” out of thin air!

Two Main “Types” of Cells Plant Cells Animal Cells

Two Main “Groups” There are two main “groups” of cells - Prokaryote (Pro=No…...No organelles!) You’ll learn about those soon enough! - Eukaryote (You=Eu and Eu=Nu… You are a eukaryote because you are made of cells with organelles and a nucleus!)

Prokaryote Cells No organelles. No nucleus. Always unicellular organisms. Examples: bacteria

Eukaryotic Cells Have organelles. Have a nucleus. Can be unicellular or multicellular. Unicellular: Yeast Multicellular: Plants and animals

Questions... Who created the first compound microscope?__________________ Who coined the term “cell”? _________________ Who started the idea that cells (life) must come from existing cells (life)? ___________________________

More Questions... What are the two “types” of cells? __________________________ __________________________ What are the two main “groups” of cells? __________________________ __________________________ What are WE? __________________________

Parts of the Microscope There are a few parts of the Compound Light Microscope which you will NEED to know!

Coarse adjustment knob Eyepiece Ocular Lens Nosepiece Body Tube Objective Lenses (3) Arm Diaphragm Coarse adjustment knob Stage with Stage clips Light Source Fine adjustment knob Base 30 30

Nosepiece Body Tube Arm Light Source Stage with Stage clips Base 31

Our objective lenses are 4x so... _______ The total power of Magnification To calculate the power of magnification, multiply the power of the ocular lens by the power of the objective. What are the total powers of magnification for each of the objectives we have on our microscopes? Our objective lenses are 4x so... _______ 10x so... _________ 40x so... _________ 32

You do not need to use the stage clips when viewing wet-mount slides! How to make a wet-mount slide … 1 – Get a clean slide and coverslip. 2 – Place ONE drop of water in the middle of the slide. Don’t use too much or the water will run off the edge and make a mess! 3 – Place the edge of the cover slip on one side of the water drop. 4 – Slowly lower the cover slip, at an angle, on top of the drop. Cover Slip Lower slowly You do not need to use the stage clips when viewing wet-mount slides! 5 – Place the slide on the stage and view it first with the red-banded objective. Once you see the image, you can rotate the nosepiece to view the slide with the different objectives. 33