Tools & Procedures

TOOLS &PROCEDURES

Honors BiologyChapter 1 Section 4

SC B-1: Students will demonstrate an understanding of how scientific inquiry & technological design can be used to pose

questions, seek answers, & develop solutions

Essential Question:

How would you compare & contrast a light microscope & an electron microscope?

Metric System used by most scientists based on certain physical

standards scaled on multiples of 10 used in SI

Common Metric Unitslength

1 meter (m) = 100 centimeters(cm)

1 meter (m) = 1000 millimeters (mm)1000 meters(m) = 1 kilometer (km)

mass1 kilogram (kg) = 1000 grams (g)1 gram (g) = 1000 milligrams (mg)

1000 kilograms (kg) = 1 metric ton (t)

more metric unitsvolume

1liter (L) = 1000milliliters( mL)1 liter (L) = 1000 cubic centimeters (cm3)

temperature0◦ C = freezing point of water100◦ C = boiling point of water

Analyzing Biological Data Data Tables

create a table to record information measured in an experiment

name the table

Biological Data new field of

BIOINFORMATICS

Computers used:To store dataTo make

sense of dataTo collect

data

Microscopes devices that

produce magnified images of structures too small to see with naked eye

Light Microscopes produce

images by focusing visible light rays through a specimen

limitations< 0.2 µ

Electron Microscope produce

magnified images by focusing beams of electrons on specimen

Compound Light Microscope up to 1000x

magnification light passes

through the specimen

uses 2 lenses specimen dead

or alive (if very small)

specimen may be stained to improve visulaizationStain entire cellStain selected

organelles or macromolecules

Parts of a Microscope Appendix D: Parts& Functions

Electron Microscopes Can produce

images 1000 times more detailed than light microscope

Types of Electron Microscopes TEMs

(Transmission Electron Microscope)

beam of e- goes thru specimen

SEMs (Scanning Electron Microscopes)

beam scan across surface of specimen

comparing Microscopes

Electron Compound Light

cannot use living cells

Very expensive higher resolution

Specimen could be living

Price not an issue Size limitations

Laboratory Techniques

Cell Cultures Take small sample of cells &

place in petri dish with nutrients & allowed to divide.

Cell Cultures might use the culture to:1. test cell responses under

controlled conditions2. study interactions between cells3. select certain cells for further

study

HeLa Cells Taken from a patient with

cervical cancer in 1950’s Cells are still growing!

Bacterial Cultures Made whenever something has

been tested for infection

Cell Fractionation Separates cells into parts

Cell Fractionation

Lab Safety Rules Always follow read through lab

completely before starting Always follow instructions Ask if you do not understand

directions Always wash your hands at end

of lab