Biology Lab - PRCC Burge Midterm Exam Questions With Correct Answers

Biology Lab - PRCC Burge Midterm Exam Questions With Correct Answers /. Steps to the scientific method - Answer-Problem, hypothesis, procedure, results, conclusion /.Explain the steps to the scientific method - Answer-Problem - Make new observation, questions concerning this observation are the PROBLEM Hypothesis - testable statement based on research, an educated guess Procedure - Test your hypothesis using deductive reasoning, uses test groups & variables Results - what happened in the experiment? Conclusion - Analysis of what happened, hypothesis is supported or rejected. /.Identify control group and why are they important - Answer-The group that does not receive the experimental treatment - serves as a baseline for comparison, helps determine if the treatment caused any observed effects /.Identify independent variable, dependent variables, and controlled variables - Answer-Independent - What is being changed/manipulated Dependent - What's being measured Controlled - What stays the same throughout /.What is a theory? - Answer-A hypothesis that has been repeatedly tested and supported /.Look over the scientific method lab report and review questions & lab notes - Answer-do that! /.pH is a measurement of what? - Answer-- a measure of the acidity of a solution, ranging in value from zero (most acidic) to fourteen (most basic) /.difference between acids and bases? - Answer-- Acids have HIGH concentration of H+, bases have a LOW concentration of H+ - Bases produce OH- ions - Acids are 0 - 6.9 pH - Bases / Alkaline are 7.1 - 14 - Neutral is 7.0 BASICALLY: More H+ = stronger ACID = LOWER pH, fewer H+ More OH- = stronger BASE = HIGHER pH /.difference between red and blue litmus paper? what do they test for? how do they react in an acid? a base? - Answer-- red litmus paper turns BLUE in presence of a BASE, doesn't change w/ neutral or acid - blue turns RED in presence of an ACID, no change w/ neutral or base /.how does neutral litmus paper react to an acid? a base? a neutral? - Answer-- turns RED with an ACID - turns BLUE with a BASE - neutral does NOT change with a neutral (stays purple-ish color) /.how does pH paper (yellow paper) react to different solutions? - Answer-- compare the color it turns to the pH scale to determine the pH value of the substance - gives specific pH measurement (unlike litmus paper) - RED for most acidic, to dark BLUE/PURPLE for most alkaline, GREEN is neutral /.What is a buffer? - Answer-mixture of a weak acid and a weak base that can combine with a strong acid or base to limit changes in pH - pH increases, buffer will release H+ to decrease pH to normal range - pH decreases, buffer absorbs H+ /.What was the neutral substance in the pH lab experiment? - Answer-Distilled water /.Review those notes for the pH stuff - Answer-do it....do it..... /.Know what a compound microscope is - Answer-same microscope we've been using: an optical instrument that uses two or more sets of lenses to achieve high magnification, allowing users to view extremely small objects that are invisible to the naked eye /.Parts of a compound microscope & their functions - Answer-Ocular - what you look through Revolving nose piece - Rotated to change one objective to another Objectives - Lens that are closest to the specimen 4x - scanning 10x - low power 40x - high power 100x - oil immersion Stage clips - hold slide in place Diaphragm and lever - under stage; control light amount Body tube - Metal casing through which light passes into ocular Arm - Connects base to ocular Stage - Where the specimen's placed