Aim – How did we develop the cell theory? Warm Up What does this quote mean?

Aim To identify trees on our campus using a dichotomous key Warm Up What is the difference between a tree and a shrub? Prediction - How many different species of trees are on our campus?

The Cell Theory All living things are made of cells. Cells are the basic units of structure and function in living things. Living cells come only from other living cells.

The Cell The smallest unit that can perform all life processes

Scientists and the Cell Theory

Aim – To be able to identify the parts of a microscope. October 29, 2014 Aim – To be able to identify the parts of a microscope. Warm Up – Why are microscopes useful tools?

Aim – To use microscopes properly Warm Up – List 3 rules for using the microscope. Did you sign up for global justice day?

Anton van Leeuwenhoek Born: October 24, 1632 Died: August 30, 1723 He is known as the “Father of Microscopy.” First to see living microbes! http://en.wikipedia.org/wiki/Anton_van_Leeuwenhoek

Anton van Leeuwenhoek Discoveries: - 1673: He looked at pond scum under the microscope and discovered small organisms he called animalcules or little animals (Protists) - 1676: discovered bacteria http://www.kent.k12.wa.us/staff/TimLynch/sci_class/chap09/lesson_protista/Protista_Lesson.html#Algae

Robert Hooke Born: July 18, 1635 Died: March 3, 1703 Wrote and published “Micrographia” http://www-groups.dcs.st-and.ac.uk/~history/PictDisplay/Hooke.html

Robert Hooke Contributions: He observed pieces of cork from the bark of a cork tree under the microscope. His observations led him to coin the word “cell.” “Cell”- means little rooms in Latin He compared the small boxes to the small rooms that monks lived in. http://www.learner.org/channel/courses/essential/life/session1/closer1.html

Matthias Schleiden Born: April 5, 1804 Died: June 23, 1881 German botanist Discovered that all plants were made of cells Contributed to the creation of the cell theory http://www.britannica.com/eb/article-9066147/Mathias-Jacob-Schleiden

Theodor Schwann Born: December 7, 1810 Died: January 11, 1882 German zoologist Concluded that all animals are made of cells. Contributed to the creation of the cell theory http://www.nndb.com/people/357/000096069/

Rudolph Virchow Born: October 13, 1821 Died: September 5, 1902 German pathologist He is known as the “Father of Pathology.” Discovered that all living cells come only from other living cells. http://en.wikipedia.org/wiki/Image:Rudolf_Virchow.jpg

The Cell Theory Major Contributors: Matthias Schleiden Theodor Schwann Rudolph Virchow

Introduction to the Microscope History Types Care Parts & functions Focusing

Microscope History Circa 1000AD – The first vision aid was invented (inventor unknown) called a reading stone. It was a glass sphere that magnified when laid on top of reading materials.

Microscope History Circa 1284 – Italian, Salvino D'Armate is credited with inventing the first wearable eye glasses.

Microscope History 1590 – Two Dutch eye glass makers, Zaccharias Janssen and son Hans Janssen experimented with multiple lenses placed in a tube. The Janssens observed that viewed objects in front of the tube appeared greatly enlarged, creating both the forerunner of the compound microscope and the telescope.

Microscope History 1665 – English physicist, Robert Hooke looked at a sliver of cork through a microscope lens and noticed some "pores" or "cells" in it.

Microscope History 1674 – Anton van Leeuwenhoek built a simple microscope with only one lens to examine blood, yeast, insects and many other tiny objects. Leeuwenhoek was the first person to describe bacteria, and he invented new methods for grinding and polishing microscope lenses that allowed for curvatures providing magnifications of up to 270 diameters, the best available lenses at that time.

Microscope History 18th century – Technical innovations improved microscopes, leading to microscopy becoming popular among scientists. Lenses combining two types of glass reduced the "chromatic effect" the disturbing halos resulting from differences in refraction of light.

Microscope History 1830 – Joseph Jackson Lister reduces spherical aberration or the "chromatic effect" by showing that several weak lenses used together at certain distances gave good magnification without blurring the image. This was the prototype for the compound microscope.

Microscope History 1872 – Ernst Abbe, then research director of the Zeiss Optical Works, wrote a mathematical formula called the "Abbe Sine Condition". His formula provided calculations that allowed for the maximum resolution in microscopes possible.

Microscope History 1903 – Richard Zsigmondy developed the ultramicroscope that could study objects below the wavelength of light. He won the Nobel Prize in Chemistry in 1925.

Microscope History 1932 – Frits Zernike invented the phase-contrast microscope that allowed for the study of colorless and transparent biological materials for which he won the Nobel Prize in Physics in 1953.

Microscope History 1931 – Ernst Ruska co-invented the electron microscope for which he won the Nobel Prize in Physics in 1986. An electron microscope depends on electrons rather than light to view an object, electrons are speeded up in a vacuum until their wavelength is extremely short, only one hundred-thousandth that of white light. Electron microscopes make

Microscope History 1931 – Ernst Ruska it possible to view objects as small as the diameter of an atom.

Microscope History 1981 – Gerd Binnig and Heinrich Rohrer invented the scanning tunneling microscope that gives three-dimensional images of objects down to the atomic level. Binnig and Rohrer won the Nobel Prize in Physics in 1986. The powerful scanning tunneling microscope is the strongest microscope to date.

Types of Microscopes Compound Microscope Dissection Microscope Scanning Electron Microscope (SEM) Transmission Electron Microscope (TEM)

Compound Microscope Compound microscopes are light illuminated. The image seen with this type of microscope is two dimensional. This microscope is the most commonly used. You can view individual cells, even living ones. It has high magnification. However, it has a low resolution.

Compound Microscope Images Paulownia Wood c.s. 200x Frog’s blood 1,000x

Dissection Microscope A dissection microscope is light illuminated. The image that appears is three dimensional. It is used for dissection to get a better look at the larger specimen. You cannot see individual cells because it has a low magnification. (also called stereo microscope)

Sunflower with moth pupa in the stem Dissection Microscope Images Head of a moth pupa 60x Sunflower with moth pupa in the stem 10x

Scanning Electron Microscope - SEM SEM use electron illumination. The image is seen in 3-D. It has high magnification and high resolution. The specimen is coated in gold and the electrons bounce off to give you and exterior view of the specimen. The pictures are in black and white.

Scanning Electron Microscope Images pigeon blood cockroach antenna

Transmission Electron Microscope - TEM TEM is electron illuminated. This gives a 2-D view. Thin slices of specimen are obtained. The electron beams pass through this. It has high magnification and high resolution.

Transmission Electron Microscope Images bacillus bacteria dividing mitochondrion

Microscope Care Always carry with 2 hands Never touch the lenses with your fingers. Only use lens paper for cleaning Do not force knobs Keep objects clear of desk and cords When you are finished with your "scope", rotate the nosepiece so that it's on the low power objective, roll the stage down to lowest level, rubber band the cord, then replace the dust cover. .

Microscope Parts Ocular lens Body Tube Revolving Nosepiece Arm Objective Lens Stage Stage Clips Coarse adjustment knob Diaphragm Fine adjustment knob Light Base

magnifies; where you look through to see the image of your specimen. ocular lens Ocular lens magnifies; where you look through to see the image of your specimen. They are usually 10X or 15X power.  Our microscopes have an ocular lens power of 10x.

supports the tube and connects it to the base arm supports the tube and connects it to the base arm

the flat platform where you place your slides stage the flat platform where you place your slides stage

coarse adjustment knob moves stage (or body tube) up and down coarse adjustment knob

after using the coarse adjustment knob fine adjustment knob small, round knob on the side of the microscope used to fine-tune the focus of your specimen after using the coarse adjustment knob fine adjustment knob

the bottom of the microscope, used for support base the bottom of the microscope, used for support base

connects the eyepiece to the objective lenses body tube body tube connects the eyepiece to the objective lenses

the part that holds two or more objective lenses revolving nosepiece the part that holds two or more objective lenses and can be rotated to easily change power revolving nosepiece

Adds to the magnification objective lenses Adds to the magnification Usually you will find 3 or 4 objective lenses on a microscope.  They almost always consist of 4X, 10X, 40X and 100X powers.  When coupled with a 10X (most common) objective lens

objective lenses eyepiece lens, we get total magnifications of 40X (4X times 10X), 100X , 400X and 1000X. The shortest lens is the lowest power, the longest one is the lens with the greatest power.  Lenses are color coded. objective lenses

push in (spring loaded) thereby protecting the lens and the slide. objective lenses The high power objective lenses are retractable (i.e. 40XR).  This means that if they hit a slide, the end of the lens will push in (spring loaded) thereby protecting the lens and the slide. objective lenses

moves it left and right, the other moves it up and down. stage clips Stage clips hold the slides in place.  If your microscope has a mechanical stage, you will be able to move the slide around by turning two knobs.  One moves it left and right, the other moves it up and down. stage clips

controls the amount of light going through the specimen diaphragm controls the amount of light going through the specimen Many microscopes have a rotating disk under the stage.  This diaphragm has different sized holes and is used to vary the intensity and size of the cone of light diaphragm

you desire and the particular objective lens in use. diaphragm that is projected upward into the slide.  There is no set rule regarding which setting to use for a particular power. Rather, the setting is a function of the transparency of the specimen, the degree of contrast you desire and the particular objective lens in use. diaphragm

light makes the specimen easier to see light

Using the Microscope The proper way to focus a microscope is to start with the lowest power objective lens first and while looking from the side, crank the lens down as close to the specimen as possible without touching it.  Now, look through the eyepiece lens and focus upward only until the image is sharp.  If you can't get it in focus, repeat the process again.  

Using the Microscope Once the image is sharp with the low power lens, you should be able to simply click in the next power lens and do minor adjustments with the focus knob.  If your microscope has a fine focus adjustment, turning it a bit should be all that's necessary.   Continue with subsequent objective lenses and fine focus each time. 

Using High Power Rotate to 40x objective, locate desired portion of specimen in the center of the field. Refocus very carefully so that the specimen is focused as sharply as possible. (Do not alter focus for the Following steps )

Using High Power Partially rotate so that 40x and 100x objectives straddle the specimen.

Using High Power Place a small drop of oil on the slide in the center of the lighted area. (Take care not to dribble on the stage.) Put the small drop of oil directly over the area of the specimen to be Examined.

Using High Power Rotate so that the 100x oil immersion objective touches the oil and clicks into place.

Using High Power Focus only with fine focus. Hopefully, the specimen will come into focus easily. Do not change focus dramatically.

Using High Power Clean up!: When you have finished for the day, wipe the 100x oil immersion objective carefully with lens paper to remove all oil. Wipe oil from the slide thoroughly with a Kimwipe. Cleanse stage should any oil have spilled on it. Recap the immersion oil container securely, replace in drawer.

Ocular lens (Eyepiece) Body Tube Nosepiece Arm Objectives Stage Stage Clips Coarse Adjustment Diaphragm Fine Adjustment Light Always carry a microscope with one hand holding the arm and one hand under the base. Base

Fill in the table on your worksheet. What’s my power? To calculate the power of magnification, multiply the power of the ocular lens by the power of the objective. What are the powers of magnification for each of the objectives we have on our microscopes? Fill in the table on your worksheet.

Comparing Powers of Magnification We can see better details with higher the powers of magnification, but we cannot see as much of the image. Which of these images would be viewed at a higher power of magnification?

Let’s give it a try ... 1 – Turn on the microscope and then rotate the nosepiece to click the red-banded objective into place. 2 – Place a slide on the stage and secure it using the stage clips. Use the coarse adjustment knob (large knob) to get it the image into view and then use the fine adjustment knob (small knob) to make it clearer. 3 – Once you have the image in view, rotate the nosepiece to view it under different powers. Draw what you see on your worksheet! Be careful with the largest objective! Sometimes there is not enough room and you will not be able to use it! 4 – When you are done, turn off the microscope and put up the slides you used.

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 from your teacher. 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 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.

Aim – To begin using a compound microscope Warm Up – List three rules we should follow when using a microscope.

Introduction to the Microscope Care Parts Focusing Students will have their microscopes out, for reference as we go through each of the steps. As an introduction, students will be asked what kinds of things they can do with this tool.

Types of Microscopes Light Microscope -  the models found in most schools, use compound lenses to magnify objects. The lenses bend or refract light to make the object beneath them appear closer. Common magnifications: 40x, 100x, 400x

Always carry with 2 hands Only use lens paper for cleaning The Light Microscope Guidelines for Use Always carry with 2 hands Only use lens paper for cleaning Do not force knobs Always store covered Teacher demonstrates how to hold the microscope, where the lens paper is located and how to use it. Students will be invited to turn the knobs and observe the stage as it moves up and down. Teacher will demonstrate how to store the microscope.

Eyepiece Body Tube Revolving Nosepiece Arm Objective Lens Stage Stage Clips This is the microscope used in class. Students will be identifying the parts on the microscopes at their desks as we go along and what their functions are. Coarse Focus Diaphragm Fine Focus Light Base

Magnification Your microscope has 3 magnifications: Scanning, Low and High. Each objective will have written the magnification. In addition to this, the ocular lens (eyepiece) has a magnification. The total magnification is the ocular x objective

2. Plug your microscope in to the outlet. General Procedures 1. Make sure all backpacks and materials are out of the aisles and off the tops of desks.  2. Plug your microscope in to the outlet. 3. Store with cord wrapped around microscope and the scanning objective clicked into place.   4. Carry by the base and arm with both hands.

Focusing Specimens 1. Always start with the scanning objective.  Odds are, you will be able to see something on this setting. Use the Coarse Knob to focus and then the fine adjustment knob until clear, image may be small at this magnification, but you won't be able to find it on the higher powers without this first step.  Do not use stage clips, try moving the slide around until you find something.

2. Once you've focused on Scanning, switch to Low Power 2. Once you've focused on Scanning, switch to Low Power. Use the Coarse Adjustment Knob to refocus. Then use the Fine Adjustment Knob to make the image crystal clear. Again, if you haven't focused on this level, you will not be able to move to the next level. 3. Now switch to High Power. (If you have a thick slide, or a slide without a cover, do NOT use the high power objective). At this point, ONLY use the Fine Adjustment Knob to focus specimens. Recap 1. Scanning --> use coarse and fine knob 2. Low power --> use coarse and fine knob 3. High power --> use fine knob only DO NOT SKIP STEPS!!!!

Your slide MUST be focused on low power before attempting this step Click the nosepiece to the longest objective Do NOT use the Coarse Focusing Knob, this could crack the slide or the lens Use the Fine Focus Knob to bring the slide Emphasize not using the coarse objective during this process, as it will crack the slides.

Drawing Specimens 1. Use pencil - you can erase and shade areas 2. All drawings should include clear and proper labels (and be large enough to view details). Drawings should be labeled with the specimen name and magnification. 3. Labels should be written on the outside of the circle. The circle indicates the viewing field as seen through the eyepiece, specimens should be drawn to scale - ie..if your specimen takes up the whole viewing field, make sure your drawing reflects that.

Cleanup Store microscopes with the scanning objective in place. 2. Wrap cords and cover microscopes.                       *Double check to make sure you didn't leave a slide 3. Place microscopes in their designated location (probably a cabinet)

Troubleshooting Occasionally you may have trouble with working your microscope. Here are some common problems and solutions. 1. Image is too dark! Adjust the diaphragm, make sure your light is on. 2. There's a spot in my viewing field, even when I move the slide the spot stays in the same place! Your lens is dirty. Use lens paper, and only lens paper to carefully clean the objective and ocular lens. The ocular lens can be removed to clean the inside. The spot is probably a spec of dust. 3. I can't see anything under high power! Remember the steps, if you can't focus under scanning and then low power, you won't be able to focus anything under high power. Start at scanning and walk through the steps again. 4. Only half of my viewing field is lit, it looks like there's a half-moon in there! You probably don't have your objective fully clicked into place..

Practice Labeling the Parts

Quiz Over the Microscope 1. When focusing a specimen, you should always start with the ___________________ objective. 2. When using the high power objective, only the ________ ___________ knob should be used. 3. The type of microscope used in most science classes is the _________________ microscope 4. What part of the microscope can adjust the amount of light that hits the slide? ______________________________

5. You should carry the microscope by the ________ and the __________ 5. You should carry the microscope by the ________ and the __________. 6. The objectives are attached to what part of the microscope (it can be rotated to click the lenses into place): _______________ ________________ 7. You should always store you microscope with the ________________ objective in place. 8. A microscope has an ocular objective of 10x and a high power objective of 50x. What is this microscope's total magnification? ____________