Bio 1406 Lab 1 Collecting and Analyzing Data

Discrete Random Variable

an integer of something counted ie. # of times a coin is tossed, number of students enrolled in class . - A quantitative value

Statistical Analysis

analyze how precise and accurate our data is.

Observations variance from one experiment to the next

known as experimental or random variables

Qualitative Value

description that is not reported in numbers ie. buffering capacity (small or large), the dog looked happy, 46% of class is female.

Standard Deviation

shows how far the measured (experiment) values deviated from each other and the mean. It measures how precise the value are. Less variation= smaller deviation.

System of Units (SI units) aka the metric system

1. used by scientist around the world 2. easy to convert from one unit to another since they are related by units of 10 nano 10^-9 micro 10^-6 milli 10^-3 centi 10^-2 deci 10^-1 Base Unit 1x 10^0 deca 10^1 kilo 10^3

Micropipetters measure volumes of 1mL or less

3 size of Micropipettes: 2-20 uL 20-200 uL 100-1000 uL (1mL = 1000 uL) to use: adjust knob to correct uL needed, attach a tip, press down plunger to first stop then place tip in liquid and slowly release to draw up the liquid. to release- push down plunger to second stop, a little air will completely empty the tip to deliver correct volume.

Pipettes measure volumes 1mL or greater

4 sizes of Pipettes: 10mL (green) 5mL (green) 2mL (blue) 1mL (blue) to use: place tip into the liquid and draw it up into pipette using thumb screw. To measure 4ml, bring liquid to 5ml, then release it to the 1ml mark.

Scientific Investigation

based on observations or information we collect using sense of sight, sound,smell, taste, and touch.

Accuracy

measure how close measured value come to true value. *measurement of the correctness of the result

Percent Error

measure of accuracy by determining how far the measured values deviate from the true value. mean= experiment measured value true (accepted ) value= desired value Percent error: absolute value of (mean-true value)/true value, then multiply by 100.

Precision

measure of consistency and is sometime referred to as reproducibility. *precise measure does not vary over several trials.

Mean

measure of precision by taking average of group of numbers. Mean= (sum of measured values)/ (# of trials)

Continuous Random Variable

positive whole number of something measured. a Quantitative Value. ie. length of hair strand

Quantitative Value

specific number ie. this soup has 185 mg sodium per serving