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Lab Skills
Microscope:
Total Magnification = Eyepiece x Objective lens
Diaphragm – Regulates Light
1 mm = 1000 μm (micrometers)
Objects are viewed upside down and backwards.
Stain (iodine or methylene blue) – makes it easier to see specimen details.
Slide Preparation: Specimen Staining…
Staining
enhances
cellular
detail.
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Graduated Cylinder: measures liquid volume

READ THE BOTTOM OF THE CURVE (MENISCUS).
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Centrifuge – spins rapidly and separates (ex. cell parts) according to density.

USE FOR THINGS YOU CAN’T SEE WITH A COMPOUND MICROSCOPE.
Microdissecting Instruments – can remove cell parts.

ex. chloroplasts, nucleus, mitochondria…

USE FOR THINGS YOU CAN’T SEE WITH A COMPOUND MICROSCOPE.
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Indicators:
Lugol’s Solution (Iodine) – turns starch blue-black
Benedict’s Solution (a blue solution) – turns sugar red-orange when heated.
Bromthymol Blue – turns acids yellow
– turns CO2 yellow (carbonic acid)
Blue Litmus – turns red in an acid
Red Litmus – turns blue in a base
pH Paper – shows acidity (pH 1 – 14: 1 = strong acid → 14 = strong base {7 = neutral})
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Chromatography – separates dissolvable pigments
based
on molecule density.
Gel Electrophoresis – sorts molecules (DNA, RNA, proteins) according to size
by using electricity to drag them through a gelatin-like
medium.
Classification
Kingdoms
Bacteria
Examples
Bacteria
E. coli
Blue-green Algae(cyanobacteria)
Archaea
extremophiles
methanogens, halophiles
Protista
Protozoa (animal-like)------------------ Amoeba, Paramecium
Algae – photosynthetic------------------ Spyrogyra, Euglena
Fungi
Absorb nutrients from
mushrooms, yeast
Environment…
Plants
Bryophytes (no-vascular tissue)
Tracheophytes (true roots, stems
moss
ferns, pine trees, oak, geranium…
and leaves)
Animals
Coelenterates (Cnidaria) – 2 layered
body cavity…
Annelids – segmented worms
Arthropods – jointed appendages/
earthworm (Lumbricus terrestus)
grasshopper
exoskeleton…
Chordates – dorsal nerve cord

humans, dogs, dolphins, etc…
Sub-phylum – vertebrates – true backbone - humans
CLASSIFICATION SYSTEM IS BASED ON EVOLUTIONARY RELATIONSHIPS
Kingdom-Phylum-Class-Order-Family-Genus-species
Most General
Most Specific
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Graphing
Hint: Spread out the numbers on your axes…

Your line(s) should take up most of the graph
grid.
Hint: When you put the numbers on the axes, the distance between
the
lines must be equal…

An axis is a number line (all numbers in
proportion).
0
1
2
3
4
5
6
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Scientific Method
1) Define Problem—Make Hypothesis
2) Set Up Experiment—Use Controls + Variables
3) Collect + Show Data
4) Make a Conclusion
5) Repeat Experiment (Observations)
Hypothesis – prediction about the outcome of an experiment
Control – used for the basis of comparison
Variable – changing condition in the experiment (ex. pH, temperature, etc…)
Example:
1) Problem: What can be used to grow plants best, Miracle Grow or Brand X fertilizer?
Hypothesis: Plants fed Miracle Grow will grow best.
2) Experiment…
(A)
Light Source
(B)
Light Source
(C)
Light Source
Controls: 3 identical plants, same size, same soil, same amount of H2O, same temperature, same amount
of light…
Variables: A – Fed Miracle Grow
B – Fed Brand X

Variable = Type of Fertilizer

Control Group = Plant C
C – No Fertilizer (control group)
3) Collect Data (i.e. plant height), Graph Data, and Analyze Data…
Week 0
Week 1
Week 2
Week 3
Plant A
10 cm
20 cm
32 cm
46 cm
Plant B
10 cm
15 cm
23 cm
31 cm
Plant C
10 cm
12 cm
18 cm
24 cm
4) Make a Conclusion: Miracle Grow works best.
Weeks
5) Repeat: This helps to validate conclusions.
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Microscope Revisited
1) Objects appear upside down and backwards.
2) Focus under Low Power first
Fine Adjustment
3) Only use fine adjustment with high power.
4) Diaphragm regulates light.
5) When adjusting the slide, things appear to move opposite
the way you move them.
6) Total Magnification = Eye Piece x Objective Lens
A = Eye Piece
B = Coarse Adjustment
C = Objective Lens
D = Diaphragm
Microscopic Measurement…

1 mm = 1000 micrometers (μm) or microns

Increase magnification, decrease field size
1.5 mm = 1500 μm
1500 μm ÷ 3 cells = 500 μm/cell
~ 3.2 mm = 3200 μm
Increased magnification decreases field of view, but increases visible detail.
 100x → 400x: 1/4 of the field of view but 4x the detail.
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Stains
(Allows you see details in the specimen better.)
Methylene Blue: used to stain animal cells (proteins)
Iodine: used to stain plant cells (cellulose/starch)
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Cell Structures Seen With Compound Microscope
Plant Cell
Animal Cell
Chloroplasts
Cell Membrane
Nucleus
Vacuole
Cytoplasm
Cell Membrane: lipid bi-layer with floating globular proteins (fluid-mosaic model);
separates the internal from the external environments.
Nucleus: “cell brain”; command and control center for the cell; contains DNA =
molecular “instructions” for cell activities.
Cytoplasm: “cell blood”; place inside the cell where the organelles are found.
Chloroplasts: plant cell “food factory”; site of photosynthesis.
Vacuole: large in plant cells; cell storage site.
Laboratory Skills: Reviewed…
1) Formulate a hypothesis or question for an experiment.
2) Distinguish between a control (remains the same) and a variable (changes).
→ In any experiment, there should only be one variable, which serves as the focus of that
experiment.
3) Recognize, collect and graph data.
4) Make predictions (inferences) based on data
5) Draw conclusions.
6) Select equipment for experiments
7) Recognize and practice laboratory safety.
8) Know the parts of the microscope.
9) Know microscopic measurement.
10) Know wet mount preparation and staining techniques.
11) Recognize cell parts.
12) Know indicators (Lugol’s, Benedict’s, Biuret, Bromothymol Blue, Litmus, pH Paper, Cobalt Chloride Paper,
etc…)
13) Measurement (Ruler, Graduated Cylinder, Thermometer, etc…)
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Biochemistry:
Element – a substance composed of a single kind of atom.

Living Things: N-CHOPS (Nitrogen, Carbon, Hydrogen, Oxygen, Phosphorus, Sulfur)
Atom – smallest part of an element
Compound – combinations of two or more different elements
Organic – “Living” – with carbon (and hydrogen).
pH: Potential of Hydrogen (H+); Acid—Neutral—Base

Acid ~ 0 – 6.9

Neutral = 7.0

Base ~ 7.1 – 14.0
Enzymes work best at certain (optimum) pHs

“-ase” suffix ending for enzymes.
Biochemicals…
Carbohydrates: 2: 1 ratio of Hydrogen to Oxygen (Carbo – Hydrates ~ water {H2O}).

Monosaccharides – simple sugars.
→ “-ose” suffix ending for sugars.
Glucose (Used for Energy)
Disaccharides – double sugars.
Maltose

Polysaccharides – many sugars (a polymer of monosaccharide monomers).
ex. Starch, Cellulose, etc…
Dehydration Synthesis: H2O is lost – Large molecule made from smaller ones…
+ H2O
Glucose
+
Glucose
=
Maltose
+ Water
Hydrolysis: H2O is added – large molecule is broken into smaller ones…
Maltose
+ Water =
Glucose
+
Glucose
Lipids: Fats, Oils & Waxes (COH) – ratio of Hydrogen to Oxygen not 2:1.

3 Fatty Acids + 1 Glycerol.

Used for energy storage (reserve) & Cell Structure.
Glycerol + 3 Fatty Acids
Dehydration Synthesis of a Lipid
Proteins: made from Amino Acids (CHON) – Nitrogen is the key distinguishing element.
Peptide Bond
Amino
Carboxyl
Group
Group
Carboxyl Group
+
H2O
Amino Acid
Amino Acid
Polypeptide
Water
Dehydration Synthesis of a Protein
Enzymes: “Lock & Key” Model…

Enzymes work best at around 37ºC; too cold they work slowly, too hot, they denature (fail).

Enzymes often work best near the neutral range of pH, except for Pepsin, which works best at a low
(acid) pH.
Substrates
Product →
Lock & Key
Model
Enzyme
Enzyme-Substrate
Enzyme →
Complex
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Summary of Life Processes:
1) Transport – materials in, out and around (circulation).
2) Respiration – getting energy.
3) Excretion – removal of metabolic waste.
4) Synthesis – building large molecules from small ones.
5) Regulation – control of activities.
6) Growth – increase size.
7) Reproduction – adding to the species population.
8) Metabolism – sum of all life processes.
9) Nutrition – obtain and use food.
10) Locomotion – movement of an organism.
11) Homeostasis – INTERNAL BALANCE OF LIFE PROCESSES.
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The Cell: Eukaryotic (with organelles) Cells…
Animal Cells:
1)
2)
3)
4)
No cell wall
Centrioles
No definite shape
Small vacuoles
Plant Cells:
1) Cell wall present
2) Have chloroplasts (organelle of photosynthesis)
3) No centrioles
4) Definite shape defined by the cell wall.
5) Large vacuoles.
Organelles: Little “organs” of the cell that help carry on its life functions…
1) Cell Membrane (Plasma Membrane): semi-permeable barrier that separates the internal (cellular) from the
external environment; regulates the passage of materials into and out of the cell (transport & excretion).

Fluid Mosaic Model: Lipid bi-layer with floating globular proteins (serve as pores).
2) Cell Wall: made of cellulose; gives support and protection to plant cells.
3) Cytoplasm: cell “blood”, liquid medium inside the cell membrane; contains organelles; involved with
intracellular transport.
4) Nucleus: cell “brain”; control and coordination center of the cell (regulation); contains DNA; directs cellular
reproduction (DNA replication and cell division).
5) Nucleolus: made of ribosomal RNA; makes ribosomes (synthesis).
6) Ribosomes: make proteins (synthesis).
7) Endoplasmic Reticulum (ER): cell transport channels.

Rough ER: possess ribosomes.

Smooth ER: lack ribosomes.
8) Golgi Bodies (Apparatus): material packaging and delivery system of the cell.
9) Vacuoles: cell storage spaces.
10) Lysosomes: contain digestive enzymes (nutrition).

Vacuole + Lysosome = Food (digesting) Vacuole.
11) Peroxysomes: contain chemicals that neutralize poisonous peroxide molecules.
12) Mitochondria: cell “powerhouse”, site of aerobic cellular respiration (energy released from glucose).
13) Chloroplasts: site of photosynthesis (food manufacturing process using sunlight).
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Cell Theory:
1) Cells are the basic structural and functional unit of all living things
2) All cells come from pre-existing cells.
Exceptions to Cell Theory…
1) First cell (abiogenesis ~ origin of life).
2) Viruses
3) Mitochondria and chloroplasts contain own DNA (genetic material).
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Cell Transport:
Passive Transport – movement of materials into or out of a
cell without the use of cellular energy.
a) Diffusion – movement of molecules from a region of
high concentration to a region of low
concentration.
b) Osmosis – diffusion of water molecules from high H20
molecule concentration to low H20 molecule
concentration.
Plasmolysis – occurs when the concentration of dissolved substances outside the cell is
greater than that found inside the cell (osmosis out).
→ Cell in a hypertonic solution (lower water molecule concentration)…
However, when the concentration of dissolved substances outside the cell is less than that
inside the cell (i.e. distilled water), water molecules diffuse into the cell, swelling it up and
causing it to burst (osmosis in).
→ Cell in a hypotonic solution (higher water molecule concentration)…
Figure showing the essential materials that must enter and leave the cell in order to
maintain homeostasis.
During photosynthesis, CO2 is recycled or diffuses in so that plant cells can make food
molecules
Active Transport – movement of materials into or out of a cell with the use of cellular energy (ATP).
Carrier proteins in the cell membrane cause
materials to move across the cell membrane
against the concentration gradient (from low to
high concentration)
Phagocytosis – process of engulfing large food items for internal
digestion in a food vacuole.
→ Lysosomes fuse with food vacuoles to help digest their contents
Pinocytosis – a smaller version of phagocytosis used to engulf small particles. (cell drinking)
Facilitated Diffusion – carrier proteins in the cell membrane cause materials to pass across the cell
membrane with the concentration gradient (from high to low concentration.)
Cyclosis – cytoplasmic streaming helps transport materials throughout the
cell.
Contractile Vacuole – organelle in freshwater (a hypotonic solution) protists that actively pumps out
water that gets into the cell by osmosis.
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Cell Locomotion:
A = Euglena (plant-like protist)
B = Amoeba (protozoan = animal-like protist)
C = Paramecium (protozoan)
← Flagellum
Cilia
← Oral Groove – used by
paramecium to ingest
food.
← Pseudopod
Euglena
Amoeba
Paramecium
Flagellum (pl. Flagella) – a long whip-like microtubule structure used to propel unicellular organisms
through the water.
Pseudopod (pl. pseudopodia) – “false foot”, cytoplasmic projections of the plasma membrane used for
crawling by some unicellular organisms.
Cilia – very short whip-like microtubule structures used like oars to propel unicellular organisms
through the water.
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Human Nutrition:
 One-way digestive tract (movement from mouth to anus by peristalsis) = alimentary canal.

Hydrolytic enzymes break down food into molecules so that it can be absorbed.
→ Amylase: breaks down starches into sugars (especially glucose).
→ Lipase: breaks down fats and oils into fatty acids and glycerol.
→ Protease: breaks down proteins into amino acids.
A = Mouth – chewing increases food surface area, promotes digestive
efficiency; salivary amylase (ptyalin) begins carbohydrate
digestion (starch → maltose).
B = Esophagus – gullet, brings food from the mouth to the stomach
C = Stomach – muscular sac that temporarily holds the food (bolus)
and churns it into a paste (chyme); acid pH allows
gastric protease (pepsin) to begin protein digestion..
D = Pancreas – produces pancreatic juice (i.e. digestive enzymes) as
well as the “nutrition hormones” insulin and glucagon.
E = Small Intestine – site of nutrient absorption; small finger-like
projections (villi) increase absorption surface
area.
F = Large Intestine – absorbs water, collects and prepares feces (solid
wastes) for egestion.
G = Gall Bladder – stores bile, which emulsifies fat into tiny droplets (increasing digestion surface area).
H = Liver – makes bile, converts excess glucose to glycogen (“animal starch”), filters the blood of
toxins, converts ammonia to urea, etc…

End products of digestion include…
→ Carbohydrates ~ glucose = cellular energy.
→ Lipids ~ fatty acids and glycerol (absorbed in the lacteals of the villi) = stored energy.
→ Proteins ~ amino acids = growth and repair.
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Human Transport…
 Closed Circulation – all blood flows through blood vessels that is pumped around the body by the heart.
→ Arteries: muscular blood vessels that carry blood away from the heart to the body cells; most
carry blood oxygenated at the lungs (except for the pulmonary arteries, which
carry deoxygenated blood from the heart to the lungs to be enriched with oxygen).
→ Veins: blood vessels with valves (prevents backflow) that carry blood to the heart from the
body cells; most carry blood deoxygenated by the body cells (except for the pulmonary
veins, which carry oxygen enriched blood from the lungs to the heart).
→ Capillaries: blood vessels one cell thick that allow for the exchange of materials to and from
the body cells, including the lungs (O2 and nutrient molecules in, and CO2 and
waste products out.
A = Aorta – takes blood away from the heart toward
the body
B = Pulmonary Artery – takes deoxygenated blood to the
lung for oxygenation.
C = Pulmonary Veins – returns oxygenated blood from
the lung.
D = Left Atrium – receives oxygenated blood from the
pulmonary veins.
E = Left Ventricle – pumps blood through the aorta to
the body cells
F = Right Ventricle – pumps blood into the pulmonary
artery.
G = Valve – prevents back flow between chambers.
H = Inferior Vena Cava – brings blood from body cells
found below the heart to the right atrium.
I = Right Atrium – receives deoxygenated blood from
the superior and inferior vena cava.

Lymphatic System: carries lymph (ICF – intercellular fluid), blood plasma leaked from
capillaries, back to the circulatory system.
→ Along with the lymph nodes, this secondary circulatory system aids in the in fighting disease
(immunity = the immune system).

Blood: mostly water and dissolved substances (nutrients, oxygen,
carbon dioxide, etc… = plasma); contains three different
kinds of cells.
→ Red Blood Cells (RBC): contain hemoglobin, which carries
oxygen; manufactured in the bone marrow..
RBC →
→ White Blood Cells (WBC): patrol the body for foreign
organisms and materials (phagocytes), and make
Platelet →
antibodies to fight against virus particles and other
substances (lymphocytes); also made in bone marrow.
→ Platelets: aid in the formation of blood clots (to plug up wounded blood vessels).

Immunity: protects body systems from invasion by foreign organisms and substances.
WBC
White Blood Cell: attack invaders (phagocytes) or
make antibodies (lymphocytes).
Antigen: foreign organism or substance that initiates
the immune response.
Antibodies – special proteins “tailor made” by
lymphocytes that attack specific
antigens.
Pathogen – disease-causing organism