Flashcards in Section 1.4 Questions Deck (19)
When collecting data and doing experiments, what system of measurement do most scientists use?
The metric system
What is the metric system?
A decimal system of measurement whose units are based on certain physical standards and are scaled on multiples of 10
1,000 meters= 1 ________
1 liter= ________ Milliliters
1 gram= _______ Milligrams
1,000 Kg= 1 _______
When scientists collect data, what are they often trying to find out?
Whether certain factors changed or remained the same
What does a graph of data make easier to recognize and understand than a table of data?
What are microscopes?
Devices that produce magnified images of structures that are too small to see with an unaided eye
What are compound light microscopes?
They produce magnified images by focusing light rays
How do chemical stains make light microscopes more useful?
They show specific structures in the cell
What are the 2 main types of electron microscopes?
Transmission electron microscopes and scanning electron microscopes
Compare how a TEM and an SEM produce images
TEMS- shines a beam of electrons through a thin specimen
SEMS- scan a narrow beam of electrons back and forth across the surface of a specimen
How must samples be prepared for observation by an electron microscope?
Preserved and dehydrated
A group of cells grown in a nutrient solution from a single original cell is called a __________
What technique do biologists use to separate one part of a cell from the other part of the cell?
What is the single most important rule for your safety while working in a laboratory?
Always follow your teachers instructions and the textbook directions exactly
Why do scientists need a common system of measurement?
Because researchers need to replicate each other's experiments and most experiments involve measurements