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53 Cards in this Set
- Front
- Back
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Types of microscopes
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Simple = magnifying glass
Electron = magnifies up to 100,000x Light = 2 types: a) Compound = magnifies up to 1,000x b) Dissecting = stereoscope |
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Difference between compound and dissecting light microscopes
3 |
Compound:
• For thin samples b/c light needs to pass through from below • reverses and invert image • direction you move the stage is opposite direction image moves Dissecting: • Specimen doesn't have to be thin b/c light comes from above • does not reverses or invert image • direction you move the stage is same direction image moves |
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Which light microscope has 2 lenses?
What are they |
Compound
1) ocular lens = 10x 2) 4 objective lenses |
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4 objective lenses
on which microscope? and they are? |
On the compound light microscope
1) Red scanning = 4x 2) Yellow low power = 10x 3) Blue high power = 40x 4) Black & which oil immersion = 100x |
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How to calculate total magnification
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Ocular lens (10x) • Objective lens
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Magnification
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degree to which an object can be enlarged
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Resolution
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• the degree of clarity
• ability to distinguish 2 separate points that are extremely close together |
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Parfocal
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once an object is in focus in one objective, it should still be somewhat in focus at the next objective
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Parcentric
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when the specimen in in the center of the field of view
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Depth of field
What is the relationship between this and total magnification? |
• when specimen has thickness so that the whole specimen cannot be in focus at the same time
• one layer will be in focus while the other is not When you increase total mag, you focus through the depth of field |
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1 Kilometers (km)
1 Centimeters (cm) 1 Millimeters (mm) 1 Micrometers (µm) 1 Nanometers (nm) = ? meters (m) |
x10^3 = 1000 meters
x10^-2 = .01 meters x10^-3 = .001 meters x10^-6 = .000006 meters x10^-9 = .000000001 meters |
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Oxidation vs. reduction
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LEO GER!
Loss of electrons oxidation Gain of electrons reduction |
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What is a reducing sugar?
Which sugars are reducing sugars? |
A sugar that gets oxidized
• loses electrons • all monosaccharides and disaccharides except sucrose |
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What tests for reducing sugars?
What color is a positive test? |
Benedict's solution
Blue ➠ brick red, orange, yellow, or green |
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How does the Benedict's Solution work?
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Contains copper sulfate CuSO4
Cu 2+ and SO4 2- Cu 2+ attacks double bond of carbonyl group of sugar, takes 2 e- Cu 2+ becomes Cu 0 (neutral) |
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3 types of polysaccharides
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1) Glycogen: stored in animal cells
2) Starch: aka amylose; stored in plant cells 3) Cellulose: stored in plant cell walls; structural polysaccharides |
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What enzyme breaks down starch?
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Amylase breaks down amylose into glucose (monosaccharides)
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What tests for starch?
What is a positive test? |
Lugol's iodine solution
Brownish-yellow / amber ➠ blue-black |
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If Lugol's iodine solution is added to a starch + amylase solution, will the test be positive or negative?
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It will be negative if all of the starch was broken down into glucose from the amylase.
It will be positive if there is still some starch that has not been broken down. |
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What solution tests for proteins?
What is a positive test? |
Buiret solution
Blue ➠ violet |
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How does Buiret Solution work?
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Contains copper sulfate CuSO4
(Just like Benedict's) Cu 2+ reacts with amine group NH2 of amino acids, taking 2 e- |
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What enzyme breaks down proteins?
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Pepsin breaks them down into amino acids
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How do detergents help lipids dissolve in water?
SO! Why is there movement in the dye when the soap is added to the milk? Why does oil float on water? |
• Lipids are nonpolar, and water is polar
• Detergents are amphipathic = both polar and nonpolar regions • Detergents dissolve the fats and mix them with the water The milk is a nonpolar lipid while the dye is polar. When the soap is added it breaks bonds in the milk and disperses the dye. • Oil is nonpolar so it won't dissolve in water • Oil is less dense so it will float on top of the water |
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Electromagnetic energy is what type of energy?
What color is it? How does it travel? Can we see the whole spectrum? |
Radiation
White light Travels in waves No! |
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Protein Quantitation lab
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Used spectrophotometer to measure protein concentration in a solution
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When electromagnetic energy hits matter it is...
What determines this? |
1) Absorbed = not visible
2) Transmitted: through object; visible 3) Reflected = into your eyes; visible The shape of the pigment |
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What is a spectrophotometer?
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Measures the light energy that is absorbed by the solutes in solution to determine the concentration of the solution
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Beer's Law
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Absorbance of light by the solutes in solution is DIRECTLY proportional to the concentration of the solutes in the solution
The higher the solute concentration, the greater the amount of solute |
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Standards
Standard curve |
Samples with known concentrations
Straight line; line of best fit |
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Black vs. white in terms of reflectance and absorbance
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Black absorbs everything and reflects nothing
White reflects everything and absorbs nothing |
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Cell Theory
3 |
1) Cell is the basic unit of life
2) All living organism are composed of cells 3) All cells are derived from pre-existing cells |
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What is the rate of diffusion affected by?
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1) Temperature = heat makes molecules move faster
2) Molecular size = smaller particles move faster |
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Passive transport
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Diffusion through a selectively permeable membrane down the concentration gradient
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What happened when the starch cell was submerged into the iodine solution?
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Since there was no iodine in the cell, it diffused across the membrane into the starch cell, turning the starch blue-black
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What happened when the cell was filled with molasses and the culture dish was filled with water
vs. when the cell was filled with water and the culture dish was filled with molasses? |
When the cell was filled with molasses the cell got heavier b/c the water from the culture dish diffused into the cell.
When the cell was filled with water the cell got lighter b/c the water diffused out of the cell into the culture dish. |
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3 tonicities and what plant and animal cells prefer
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Animal:
Hypotonic solution = lysed Hypertonic solution = shriveled Isotonic solution = normal Plant Hypotonic solution = turgid (normal) Hypertonic solution = plasmolyzed (shriveled) Isotonic solution = flaccid |
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What temperature and pH do enzymes work optimally under?
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37°C
pH 6-8 |
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What is benzoquinone?
Where was it in the lab? |
Product of an enzyme reaction
antimicrobial compound that protects fruits and veggies In the potato extract |
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What 2 substrates produce benzoquinone?
What enzyme breaks down these substrates? |
Catechol + O2
Catechol oxidase Catechol and catechol oxidase are in the flesh of fruits and veggies, when the flesh is cut the addition of O2 produces benzoquinone |
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Which substrate is a competitive inhibitor to catechol?
What is the difference between the two? |
Hydroquinone
Catechol: OH is on carbons 1 and 2 Hydroquinone: OH is on carbons 1 and 4 |
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What does a high absorbency mean from the spectrophotometer?
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It means that there is a lot of benzoquinine because this is what's absorbing the light
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Why was the enzyme incubated before adding the substrate?
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If the substrate was added first the enzyme (catechole oxidase) would have had some time to work upon the substrate (catechol) before the temperature took effect upon the enzyme.
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Autotroph vs. heterotroph
Autotroph examples |
Autotroph = self feeder; able to produce their own food/sugars
• plantae, protists, cyanobacteria (blue-green algae) Heterotroph = feeds on other organisms |
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Photosynthetic equation
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6 CO2 + 12 H2O ➞ C6H12O6 + 6 O2 + 6 H20
➞ = sunlight |
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In which organelle does photosynthesis occur?
What are the 3 families of pigments that are here? What are their purpose? |
Chloroplast
1) Chlorophyll a 2) Chlorophyll b 3) Carotenoids = orange, red, yellow The pigments absorb light to produce sugars. Each pigment absorbs/reflects different colors so that the plant can utilize the entire light spectrum |
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What is Thin Layer Chromatography (TLC)?
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A technique used to separate components in a mixture so that they can travel up the slide
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What affects this process? 2
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1) Affinity for absorbent
• lower the affinity, the further pigment will travel up the slide • higher the affinity, the more pigment will stick to the slide 2) Solubility (high) • higher the solubility, further pigment will travel b/c it is more attracted to the solvent than the slide |
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Rf value
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Calculates the components of a mixture
Pigment (mm) / solvent (mm) no units, they cancel out Will always be < 1 b/c solvent always travels further than pigment |
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Absorption Spectrum
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Determines the wavelengths of light a chemical best absorbs
High peak = high absorbance = don't see color Low = low absorbance = see color |
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Relationship between absorption and transmittance
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Inverse relationship
If there is a 30% absorption, there will be a 70% transmittance |
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What happens when CO2 is blown into H2O + bromthymol blue
How does sunlight affect the solution? |
H2O + CO2 ➞ H2CO3 carbonic acid
Bromthymol blue turns from blue to green to yellow as acidity increases Sunlight turns the solution back to blue |
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What is a molecule that has both polar and non-polar regions?
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Amphipathic
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What is amylose
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Starch
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