Electron Microscopes A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning it with a focused beam of electrons. A transmission electron microscope (TEM) is a type of electron microscope in which an image is derived from electrons that have passed through the specimen.

Scanning Electron Microscope (SEM)

Transmission Electron Microscope (TEM)

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.

Cheek Cells

Cork Cells

Onion Cells

An efficiency apartment is a one-room apartment An efficiency apartment is a one-room apartment. This one room is where you sleep, eat, shower, and entertain your guests. It all happens in one room. It is a simple way of living in a small space. A mansion is a large, complex living space with many separate rooms. There are rooms for cooking, eating, sleeping, bathing, reading, watching TV, entertaining guests, exercising, and storage. The rooms in a mansion are constructed for the specific things you would like to be able to do. Cells can be as simple as a one-room efficiency apartment or as complex as a mansion.

Prokaryotic Cells Vs. Eukaryotic Cells

Prokaryotic Cells Vs. Eukaryotic Cells Prokaryotes: Have no nucleus Circular DNA No membrane-bound organelles Relatively small Reproduce quickly Eukaryotes: Have a nucleus Linear DNA Membrane-bound organelles Relatively large Reproduce slowly

Organelles Activity With a partner, work on the organelle chart. You should use your prior knowledge and the word bank on the back in order to complete the chart. If you finish early you may continue working on your project. If you do not finish it is homework, you will need it completed for tomorrow’s activity.

Plant Cells Vs. Animal Cells Have a nucleus Linear DNA Membrane-bound organelles Relatively large Reproduce slowly Have a cell wall and a cell membrane Have mitochondria and chloroplast Animal: Have a nucleus Linear DNA Membrane-bound organelles Relatively large Reproduce slowly Have a cell membrane Have mitochondria

Bacteria The cell wall in a bacteria is different than that in a plant. It is made of peptidoglycan, whereas in a plant it is made of cellulose.

Characteristics of Life Cell vs. Virus Characteristics of Life Cell Virus Growth Homeostasis Metabolism Evolution Reproduction Genetic Material Are viruses alive? Why or why not? https://www.youtube.com/watch?v=PHp6iYDi9ko