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Light Microscope - A light microscope uses focused light and lenses to magnify a specimen, usually a
cell
Compound Microscope - an optical instrument for forming magnified images of small objects,
consisting of an objective lens with a very short focal length and an eyepiece with a longer focal length,
both lenses mounted in the same tube
Electron Microscope - a microscope with high magnification and resolution, employing electron
beams in place of light and using electron lenses
Cell Theory - a basic tenet of modern biology, first stated by Matthias Schleiden and Theodor
Schwann in 1838–39, that cells are the basic units of structure and function in living organisms
Macromolecules – Large molecules that form when smaller molecules join
Nucleic Acid – Long chains of nucleotides join together
Protein – Long chains of amino acid molecules
Lipid – Form cell membranes
Carbohydrate – Long chains of sugar molecules
Cell Membrane – The cell membrane protects the inside of the cell from the environment outside the
cell
Cell Wall – The cell wall protects a cell from attack by harmful organisms
Cytoplasm – Cytoplasm is a fluid inside the cell
Cytoskeleton – The cytoskeleton forms a framework inside the cell
Organelle - a specialized part of a cell having some specific function; a cell organ
Nucleus – The nucleus is the part of a eukaryotic cell that directs all cell activity and contains genetic
material
Chloroplast – Chloroplasts process light energy, water, and carbon dioxide to make glucose and
release oxygen
Prokaryotic Cell - a cell lacking a true membrane-bound nucleus
Eukaryotic Cell - a cell with a true nucleus; a cell with a nuclear membrane and organelles
Mitochondria – Mitochondria are the sites of energy processing
Vacuole – Vacuoles store food, water, and waste material
Lysosome - a cell organelle containing enzymes that digest particles and that disintegrate the cell after
its death
Endoplasmic Reticulum – An endoplasmic reticulum that has ribosomes attaches is a site of
production proteins
Golgi Apparatus – The Golgi apparatus prepares proteins for specific jobs
Ribosomes – Important molecules made by ribosomes are protein

All plants and animals in the world are made of cells
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Cells are like bricks, but cells are alive
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Mitochondria power the cell
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Yogurt and cheese are made of bacteria mold cells
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During metamorphosis, all the cells get reorganized
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There is no such thing as a one-cell boy
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Genes are made of DNA
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Seeds are plant cells that are all dried out
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Cells have different jobs
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Prokaryotic

Similarities

Eukaryotic

Have genetic material not
surrounded by a membrane

Have a cell membrane

Make up plants, animals, fungi,
and protists

Do not have many cell parts

Have a cytoskeleton

Have genetic material
surrounded by a membrane

Are bacteria

Have cytoplasm

Contain membrane surrounded
organelles

Some have a cell wall

Prokaryotes cells are the simplest of all the cells
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Eubacteria are common types
that occur all around us, usually they are on surfaces and in the soil
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Archaebacteria are thought to be some of the oldest
life forms on earth
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That means they have to rely on other
organisms to provide them with food
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When most people hear the word bacteria, they think of something that is bad for you
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Some bacteria actually help you! Bacteria are used to make food, such as cheese
and yogurt, and they can also help us break down harmful substances in the environment
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Some bacteria live inside the guts of
animals and help them to digest food
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Salmonella bacteria can cause food
poisoning, and certain types of bacteria are responsible for other infections
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The most familiar type of microscope is the standard light microscope
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The arm is the correct place to grip the microscope when carrying it
while supporting the base with the palm of your other hand
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The stage has a hole in its center to allow light to pass through, so specimens
must be positioned over the top of this hole
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It has a range of 1 to 5, with 5 being the most light
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Light microscopes use either a bulb or a mirror as their light source
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The switch for this light is usually found on the base of the microscope, and
sometimes on the power cord
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The shortest of the three objectives is the scanning-power objective lens, and has a power of 4x
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The high-power objective lens has a magnification of 40x
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The eyepiece is usually 10x
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You can
easily switch objectives by turning the rotating nosepiece
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You will use this primarily to focus on
your specimen
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The fine adjustment knob is also for minute focusing
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Understanding Cells
Microscopes enable us to see the tiny basic units of all living things
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Matthias Schleiden and Theodor Schwann realized that plant and animal cells have similar
features
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The cell is the
smallest unit of life
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Basic Cell Substances
Macromolecules form when many small molecules join
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The structure of a water molecule makes it ideal for dissolving many other substances
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Nucleic acids form when long chains of molecules called nucleotides join
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The macromolecules that are necessary for nearly everything cells do are proteins
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Some proteins help break down nutrients in
food
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Macromolecules that do not mix with water play an important role as protective barriers in
cells
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Carbohydrates store energy and provide structural support
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Cell Shape and Movement
A cell is made of different structures that work together and keep a cell alive
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A cell membrane is mostly made of phospholipids and proteins
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Plant cells, fungal cells, and some types of bacteria have cell walls
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Long, tail-like appendages called flagella whip back and forth and move a cell
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Most water in a cell is in the cytoplasm, a fluid that contains salts and other molecules
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Cell Types
With advanced microscopes, scientists discovered that all cells can be grouped into two typesprokaryotic and eukaryotic
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Plants, animals, fungi, and protists are made of one or more eukaryotic cells
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Cell Organelles
The nucleus is the part of a eukaryotic cell that directs cell activities and contain genetic
information stored in DNA
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Proteins are made in small structures called ribosomes
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Energy is released during chemical reaction that occur in the mitochondria
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Chloroplasts are membrane-bound organelles that use light energy and make glucose from
water and carbon dioxide
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The Golgi apparatus prepares proteins and packages them into ball-like structures called
vesicles
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Vacuoles are organelles that stores food, water, and waste material
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Two inventors of early microscopes were Anton van Leeuwenhoek and Robert Hooke
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Types of Microscopes
One characteristic of all microscopes is that they magnify images
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Another characteristic of microscopes is resolution-how clearly the magnifies image can be
seen
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A light microscope that uses more than one lens to magnify an image is called a
compound microscope
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Light microscopes can enlarge images up to 1500 times their original size
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Because objects must be mounted in plastic and then slices very thin, only dead
organisms can be viewed with an electron microscope
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SEMs microscopes usually are used to study the surface of an object

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