gel Flashcards
What is gel electrophoresis?
A technique used to separate DNA fragments based on their size and charge.
What are Short Tandem Repeats (STRs)?
Short, repeated DNA sequences (2–6 base pairs long) found in non-coding regions of the genome.
Why are STRs useful?
They are useful for:
* DNA fingerprinting (forensics)
* Paternity testing
* Identifying genetic relationships
What are restriction enzymes?
Enzymes that cut DNA at specific sequences, creating fragments of different sizes.
How do restriction enzymes function in bacteria?
They act as a defense mechanism against viruses.
What are the two types of cuts made by restriction enzymes?
Sticky ends and blunt ends.
What is an example of a restriction enzyme that creates sticky ends?
EcoRI.
Fill in the blank: DNA is ______ from cells before gel electrophoresis.
extracted
What happens during the preparation of the agarose gel?
Agarose powder is dissolved in an electrophoresis buffer, heated, poured into a mold, and cooled to create wells.
What is the purpose of loading dye in gel electrophoresis?
To make DNA samples visible.
What is the function of a DNA ladder in gel electrophoresis?
Provides a reference for fragment size.
What happens to DNA when an electric current is applied during gel electrophoresis?
DNA moves toward the positive electrode (anode) because it is negatively charged.
What is the relationship between fragment size and movement in gel electrophoresis?
Smaller DNA fragments move faster and farther than larger fragments.
What is used to visualize DNA bands after electrophoresis?
A fluorescent dye (e.g., ethidium bromide or GelRed).
What does a brighter band indicate in gel electrophoresis?
More DNA is present.
What is one application of gel electrophoresis in forensic science?
DNA profiling used in crime scene investigations.
What is a medical diagnostic use of gel electrophoresis?
Identifying genetic mutations linked to diseases.
What is one use of gel electrophoresis in evolutionary biology?
Analyzing DNA similarities between species.
What is the role of gel electrophoresis in paternity testing?
Compares child and parent DNA patterns.
