Chapter 3 Biological tools and Instrumentation

Taxonomic (Dichotomous) Key 1a. Is the organism unicellular -go to step 2 1b. Is the organism multicellular -go to step 3 2a. Is the organism prokaryotic -kingdom Monera 2b. Is the organism eukaryotic -Kingdom Protista

Scientific Method An systematic approach to problems solving: An systematic approach to problems solving: 1. Defining the problem 1. Defining the problem “ By doing Background Research ” “ By doing Background Research ” 2. Formulating a hypothesis 2. Formulating a hypothesis 3. Testing the hypothesis 3. Testing the hypothesis 4. Recording observations 4. Recording observations 5. State a conclusion 5. State a conclusion

Three types of Experiments 1. ****Controlled Experiments**** 2. Trial and Error 3. Open Ended

Defining the problem Defining the problem “By doing Background Research ” “By doing Background Research ” Hypothesis – Hypothesis – Experimentation Experimentation 1. Control group (no change) 2. Experimental group (make change) control = control = variable = variable = * State a conclusion

Defining the problem Defining the problem Hypothesis – a possible explanation for events. Hypothesis – a possible explanation for events. Experimentation (Testing the hypothesis) Experimentation (Testing the hypothesis) 1. Control group (no change) a source for comparison 1. Control group (no change) a source for comparison 2. Experimental group (contains 2 variables) 2. Experimental group (contains 2 variables) *Independent Variable (Manipulated) *Dependent Variable (responding) #’s State a conclusion State a conclusion

Theory - explanation supported by experimental evidence. Theory - explanation supported by experimental evidence. Scientific Law - is a statement that describes some aspect of a phenomena that is always true. Scientific Law - is a statement that describes some aspect of a phenomena that is always true.

Microscopes 1.Simple Microscopes 2.Dissecting microscope 3.Compound Microscope 4.Phase Contrast Microscope 5.Electron Microscope SEM TEM

Instrumentation A. Simple microscope - magnifying glass 1 –uses 1 lens B. Compound light microscope B. Compound light microscope 1- uses two lenses 1- uses two lenses a) ocular (eyepiece) 10x a) ocular (eyepiece) 10x b) objective b) objective - low power, 10x - low power, 10x - high power, 40x - high power, 40x

Compound Light Microscope Magnifies 50x to 500x the original size Magnifies 50x to 500x the original size Used to look at the whole cell and organelles like the nucleus and chloroplast Used to look at the whole cell and organelles like the nucleus and chloroplast

Adjustments: Coarse adjustment – used to focus under low power Coarse adjustment – used to focus under low power Fine adjustment – used to focus under high power ONLY Fine adjustment – used to focus under high power ONLY Used to “fine tune” the image Used to “fine tune” the image

Total Magnification: Magnifications: ocular = 10x low power objective = 10x low power objective = 10x high power objective = 40x high power objective = 40xFormula: ocular x objective = total magnification High power magnification is? 10 x 40 = 400x 10 x 40 = 400x

Imagery: When placing a slide under the objective lens, the image appears: When placing a slide under the objective lens, the image appears:-magnified -upside down -inverted (backwards). Ex: e  Ex: e  F  F 

Imagery: (as seen under low power) e  F  F e

Imagery: Field of View (fov) Scanner fov = 4000 um F F Low fov=2000 um What is the size of the “F”?

Imagery: Field of View (fov) F 4000 um

Electron Microscopes Advanced microscope magnifies 250,000x Advanced microscope magnifies 250,000x the original size the original size Allows for detailed observation of small organelles within the cell. Allows for detailed observation of small organelles within the cell. Like the mitochondria and lysosomes. Like the mitochondria and lysosomes.

Dissecting Microscope Gives the viewer a 3-D image of the organism Gives the viewer a 3-D image of the organism Used in the dissection of small animals and plants Used in the dissection of small animals and plants Low magnification Low magnification 1-10x 1-10x

Other Biological Tools Separation Techniques Centrifuge Centrifuge Chromatography Chromatography Gel electrophoresis Gel electrophoresis Dialysis Tubing Dialysis Tubing Dissection and micro dissection instruments Dissection and micro dissection instruments Stains Stains Indicators Indicators System International System International

Separation Techniques Centrifuge: Separates of solutions based on each parts density Centrifuge: Separates of solutions based on each parts density Chromatography: Separates Solute from Solvent Chromatography: Separates Solute from Solvent Electrophoresis: separates macromolecules-either nucleic acids or proteins-on the basis of size, electric charge, and other physical properties Electrophoresis: separates macromolecules-either nucleic acids or proteins-on the basis of size, electric charge, and other physical properties Dialysis Tubing Dialysis Tubing

Centrifuge Separates of solutions based on each parts density Separates of solutions based on each parts density

Gel Electrophoresis

Electrophoresis Opposite charges at each side causing sample to move Smaller DNA fragments move faster and further Smaller DNA fragments move faster and further

IV. Electrophoresis

Electrophoresis: separates nucleic acids or proteins-on the basis of size, electric charge, and other physical properties separates nucleic acids or proteins-on the basis of size, electric charge, and other physical properties

Chromatography Separates Solute from Solvent Separates Solute from Solvent Distance traveled by the solute (ink) Distance traveled by the solvent (liquid) Rf=

Thin-Layer Chromatography (TLC)

Chromatography

Retention Factor Rf

Dissection Instruments Tools used to perform dissection of Tissues/ organisms Tools used to perform dissection of Tissues/ organisms Dissecting scope sometimes used Dissecting scope sometimes used

Micro dissection Instruments Micro dissection Instruments Tools used to perform dissection of individual cells or the removal of cell organelles. Tools used to perform dissection of individual cells or the removal of cell organelles. Most commonly used with the Electron microscope (greatest magnification). Most commonly used with the Electron microscope (greatest magnification).

Staining Techniques The use of solutions to make it more possible for an observer to see structures of a cell easier under a microscope The use of solutions to make it more possible for an observer to see structures of a cell easier under a microscope 1. Iodine- used primarily to stain nucleus of animal cell. 1. Iodine- used primarily to stain nucleus of animal cell. 2. Methylene blue- used primarily to view chloroplasts and the cell wall of a plant cell. 2. Methylene blue- used primarily to view chloroplasts and the cell wall of a plant cell.

Staining Techniques

Indicators Designed to detect specific materials Designed to detect specific materials INDICATORSDETECTS INDICATORSDETECTS Iodine/ Lugols solution  starch Iodine/ Lugols solution  starch Benedicts solution  Glucose Benedicts solution  Glucose Biuret solution  proteins Biuret solution  proteins Bromomethyl blue  carbon dioxide Bromomethyl blue  carbon dioxide and Lime water and Lime water Litmus paper  acids or bases Litmus paper  acids or bases

SI: System International, The Metric System The most common system of measurement used by scientists is the metric system. The metric system is based on the unit 10. (Based on multiples of ten) The metric system has many basic units for its’ measurements. (Length = is a meter, etc.) The most common system of measurement used by scientists is the metric system. The metric system is based on the unit 10. (Based on multiples of ten) The metric system has many basic units for its’ measurements. (Length = is a meter, etc.)

SI: System International, The Metric System Think of the basic units as Suffixes. Think of the basic units as Suffixes. *Meter, Gram. Second, Liter, Degree Celsius, Think of the abbreviations as prefixes: Think of the abbreviations as prefixes: Kilo =1000 Kilo =1000 Centi = 100 th Centi = 100 th Milli = 1000th Milli = 1000th

ALLLL DONE!