Lab (1)+(2)+(3)_General Biology PDF

GENERAL BIOLOGY LAB (1) Biology Lab Safety, Lab Notebook, Basic Biology Laboratory Equipment College of Applied Sciences Biology Department  General Safety Rules 1. Listen to or read instructions...

GENERAL BIOLOGY LAB (1) Biology Lab Safety, Lab Notebook, Basic Biology Laboratory Equipment College of Applied Sciences Biology Department  General Safety Rules 1. Listen to or read instructions carefully before attempting to do anything. 2. Place bags, lab coats, books etc. in specified locations NEVER ON THE BENCH TOPS. 3. There are many different types of protective glove, Use the correct ones for the job you will be doing. 4. Never eat, drink or smoke in a laboratory 5. If you have an allergy to lab materials or suffer from a Medical condition(eg: diabetes or epilepsy), ensure that your supervisor knows. 6. Do not touch broken glassware with your hands, Dispose off broken glass in appropriate receptacles. 7. Do not dispose of hazardous or noxious chemicals in laboratory sinks. Use proper containers in fume hood.  General Safety Rules 8- Dispose of all biological waste into appropriate place (Orange Biohazard bags). 9- Keep your workplace tidy, Clear up waste, and washing up things. 10 - Clean up your lab area at the conclusion of the laboratory period. 11-Remove your gloves before using telephone, and leaving the laboratory. 12- After handling chemicals and before leaving the lab, always wash your hands with soap and water.  What are the general hazards in a laboratory? ▪ Fire. ▪ Breakage of glassware. ▪ Sharps. ▪ Spillages. ▪ Pressure equipment & gas cylinders. ▪ Extremes of heat & cold. ▪ Chemical hazards. ▪ Biological hazards. ▪ Electrical ▪ Radiation.  Dressing for Lab Tie back long hair Don’t wear sandals or open Roll up loose sleeves. shoes Wear laboratory coats Protective disposable glove Appropriate safety glasses  General Laboratory Tools No Equipment Names Function 1- Beaker To measure liquids 2- Erlenmeyer Flask To measure liquids and mix them 3- Mortar and pestle used to grind solids into fine powders to speed the mixing or reaction process. 4- Graduated Cylinder To Accurately measure 5- Test Tube To mixing liquids to observe their reaction. 6- Thermometer Used to measure temperature in degrees Celsius or Fahrenheit. 7- Dropper / Micro To transfer small amount of liquids pipette 8- Wash bottle Used to rinse or wash with water or alcohol 9- Spatula Used to transfer solid chemicals 10- Petri Dish To grow bacteria and fungi 11- Test tube rack Used to hold test tubes No Equipment Names Function 3 1- Scissors Cuts tissue during dissection. 2- Microscope Slide Used to prepare specimen for Microscope examined. 1 2 4 3- Cover slip Cover spedmen on the slide. 4- Watch glass Used to cover an evaporating dish or beaker. 5- Teasing Needle Used as a probe in dissection. 6- Scalpel Make precise cuts. 5 6 7 8 7- Stirring rod Used to stir, assist in pouring liquid. 9 10 8- Glass Dropper Bottles Store and disperse a variety of liquids. 9- Bunsen burner or Used for heating. alcohol lamp 10- Filter Paper Used to absorbed an extra liquid from the material. 11- Slide Box Used to store slide for long time. 12- Staining dishes Used for staining chromosome or washing with 12 alcohol or water. 11  General Genetics Equipment's No Equipment Names Function 1- Sensitive Balance Used to weight small amount of solid chemical or powder. 2- Magnetic Stirrer Used to mixing and keeping the chemical solutions and mixtures at a certain time and temperature by the help of a magnetic bar. 3- Centrifuge Used in cell culture, nucleic acid isolation to separate two liquids in emulsion form or suspended solids in liquids. 4- Incubator Used to grow microbiological cultures or cell cultures, and maintains optimal temperature, humidity and other conditions such as carbon di oxide and oxygen content of atmosphere inside. 5- Autoclave Used to sterilize materials and media under pressure and steam. 6- Thermo Water Bath Uses water to heat or maintain a constant temperature of laboratory materials or equipment. 7- Electrically heated Used to remove water or other solvents from chemical samples and to ovens dry laboratory glassware. 8- pH meter Is an electronic device used for measuring the pH. The pH will indicate if the solution is acidic or basic  General Genetics Equipment's Sensitive Balance Magnetic Stirrer pH meter Image result for water bath Centrifuge Incubator Autoclave Water Bath Dry ovens  GENERAL BIOLOGY LAB (2) Scientific Investigation Laboratory College of Applied Sciences Biology Department  Scientific Investigation Laboratory Questions and Hypotheses Exercise Designing Experiments to Test Hypotheses Exercise Designing an Experiment Exercise Presenting and Analyzing Results Exercise Interpreting and Communicating Results  The question formulated from the observation must be logical and answerable. Hypotheses developed from questions must be based on relevant information, testable, and falsifiable. Experiments should be designed to minimize variability, meaning only small details/variables (preferably only one) should be altered to test the hypothesis. These controlled experiments are best when only one variable is changed. Lastly experiments must be repeatable to help ensure there is no bias in the results.  Questions and Hypotheses Exercise 1. What is the hypotheses? 2. What is the dependent variable? 3. What is the independent variable? 4. What were the constant variables? 5. What was the control treatment? 6. How many replicates were conducted? Why? Controlled variables are the aspects of the experiments that remain the same through every variation of the experiment. For example, a researcher testing the effect of soil conditions on plant growth will give each plant the same amount of water, sunlight, air conditions, temperature etc. The independent variables are the aspects of the experiment that the researcher changes in order to test the hypothesis. In the above example, the differing soil condition is the independent variable. Ideally only one variable is changed when addressing a hypothesis. The dependent variables are the aspects of the experiment that are measured, and the data obtained is carefully recorded. For example, the researcher measuring the effect of soil What was the control treatment? In biological experimental, the cell or any organ in it would be that sample in the group that get no treatment in an experiment. Say there is a scientist testing how a new drug causes cells to grow?! One group, the experimental group would receive the drug and the other would receive a placebo. The group that received the placebo is the control group  How many replicates were conducted? Why?  Replicate: A replicate is one experimental unit in one treatment. The number of replicates is the number of experimental units in a treatment.  Normally we design experiment with 3 replicates, each replicate has like 10 samples/treatment (so total number of samples n = 30/treatment). Then we average the results of these 10 samples to get 1 number/replicate and use these 3 numbers/treatment to performing statistical analysis.  Replicates can be used to measure variation in the experiment so that statistical tests can be applied to evaluate differences. Averaging across replicates increases the precision of gene expression measurements and allows smaller changes to be detected.  Presenting and Analyzing Results Exercise All scientific results must eventually be analyzed and presented to others. A. Basics Numerical results must be recorded and presented with proper units, an estimate of uncertainty and the correct number of significant figures. B. Error analysis and propagation The uncertainty recorded for a measurement depends on a careful analysis of all the factors that may cause the measurement to deviate from the true value, either randomly or systematically. Error propagation methods are used to find the uncertainties in any quantities calculated using the raw measurements. C. Curve fitting It is often desirable to compare experimental data with a function derived from theory. This usually requires choosing some parameters in the theoretical expression so as to best describe the data. That is, the observations (xi, yi) are claimed to follow a function y=f(x) provided that the constants in f(x) are chosen properly. The usual procedure is to adjust the parameters to minimize the sum of the squares of the differences between the expected value of the function and the actual data:  Presenting and Analyzing Results Exercise D. Testing agreement Because of the uncertainties in all data, deciding whether or not the observations agree with expectations becomes a problem in probability estimation. The basic idea is to decide how likely it is that the observed deviations are due to chance, rather than a real difference. If the deviation is large it becomes so unlikely to occur by chance that we claim the difference is real. E. Graphing Graphs are used in the analysis of data and the presentation of results to others. Certain conventions, which differ among the disciplines, have been developed to ensure that graphs are clear and meaningful for their intended use.  Interpreting and Communicating Results  It is important to share what you have learned with others.  Scientists often find solutions to problems by knowing the results of other scientists' experiments.  Communicating your results is often the first step to clearly identifying a problem and beginning to think about possible solutions.  There are four frames of references for interpreting test scores are explained: Ability, growth, norm, and criterion referenced interpretations.  GENERAL BIOLOGY LAB (3) Microscopes and Cells Laboratory College of Applied Sciences Biology Department Microscopes and Cells Laboratory The Compound Light Microscope Exercise Basic Microscope Techniques Exercise The Stereoscopic Microscope Exercise The Organization of Cells  Type of Microscope A) Compound Microscope. B) Electron Microscope. C) Fluorescent Microscope.  Microscope Structure HELP SCIENTISTS STUDY OBJECTS & MAGNIFIES OBJECTS LIVING THINGS (MAKES OBJECTS TOO SMALL TO LOOK BIGGER). SEE WITH THE NAKED EYE.  PARTS OF MICROSCOPE A general biological microscope mainly consists of an : 1.Ocular (lens) eyepiece: the lens of the microscope that you look through. 2. Course adjustment: the large knob on the microscope that you turn to bring the object into focus. 3. Fine adjustment: the small knob on the microscope that brings the image into focus. 4. Arm: the part of the microscope supporting the body tube. 5. Body tube: the part that holds the eyepiece and the objective lenses. 6. Nosepiece: the part at the bottom of the body tube that holds the objective lenses and allows them to be turned.  PARTS OF MICROSCOPE 7. High power objective lens: the lens that magnifies the object the greatest amount. (usually 40x). 8. Low power (scanner) objective lens: the lens that magnifies the object the least amount (usually used to find the object; magnifies only 3x or 4x). 9. Middle power objective lens: the lens that usually magnifies the object more than the scanner lens, but less than the high power lens (usually 10x to 20x). 10. Stage: the flat part below the objectives lens where the slide is placed. 11. Clip: the part that holds the slide in place so it doesn’t move. 12. Diaphragm: the part that controls the amount of light entering the field of view.  PARTS OF MICROSCOPE 13. light source: the lamp (or mirror) under the stage that sends light. through the object being viewed. 14. base: the bottom part that supports the rest of the microscope. The Stereoscopic Microscope Exercise Compound VS Electron Microscopes Fluorescence Microscope Fluorescent light, laser. X 400-700 nm Living or dead Time- consuming and need Biological fluorescent stains Expensive  The Organization of Cells Most organisms have functional parts with five levels: cells, tissues, organs, organ systems and whole organisms. Based on the organization of their cellular structures, all living cells can be divided into two groups: prokaryotic and eukaryotic (also spelled procaryotic and eucaryotic). Animals, plants, fungi, protozoans, and algae all possess eukaryotic cell types. Only bacteria have prokaryotic cell types.