Microscope, Cells And DNA Flashcards
What is a UNICELLULAR organism?
It is an organism that consists of one cell
What is a MULTICELLULAR organism?
An organism that consists of two or more cells.
What is the unit of measurement used to measure a cell?
Micrometers (μm)
What is the function of the nucleus?
To control the activities of the cell.
What does the nucleus contain?
It contains genetic energy in the form of DNA
How is DNA contained?
DNA is contained in long thread-like structures called chromosomes. Chromosomes contain genetic information which allows us to grow and develope
What is DNA profiling?
It involves taking a sample of DNA and cutting it into fragments. These fragments are then separated by electricity on a gel by a process called GEL ELECTROPHORESIS.
How does GEL ELECTROPHORESIS work?
The negatively charged molecules move through the gel towards the positive electrode.
The gel contains minute holes, so it acts like a sieve.
Small molecules move quickly;
Large molecules follow behind.
Shorter fragments of DNA move through the gel quicker than longer fragments .
DNA fragments can be stained with a dye. DNA from a crime scene can be used with DNA from suspects to identify a criminal.
What does an eyepiece lens do?
Magnifies the specimen
Course adjustment control
Used to focus on low power
Fine adjustment control
Used to focus on medium and high power
Objective lens
Magnifies the specimen
Nosepiece
Allows the objective lens to be changed
Stage clips
Holds the slide in place on the stage
Diaphragm
Controls amount of light entering condenser
