lab 5 DNA Fingerprinting

RESTRICTION DIGESTION ANALYSIS

A method used in molecular biology to analyze DNA or RNA by cutting it at specific sequences with restriction enzymes. As you learned in the previous chapter, the enzymes then digest (hydrolyze) the sugar-phosphate backbone of the DNA molecule at that site—called a “restriction site”—acting like molecular scissors, they cut the DNA backbone at or near a specific sequence of base pairs.

Restriction digestion continued

If a specific restriction site occurs in more than one location on a DNA molecule, a re-striction enzyme will make a cut at each of those sites resulting in multiple fragments, as you learned. The length of each fragment will depend upon the location of restriction sites contained within the DNA molecule.

agarose gel electrophoresis

A technique used to separate DNA, RNA, or proteins based on their size and charge by applying an electric field to a gel matrix made of agarose. Over a period of time smaller fragments will travel farther than larger ones. Fragments of the same size stay together and appear to migrate as single “bands” of DNA.

Electrophoresis

A laboratory technique used to separate charged molecules, such as DNA or proteins, based on their size and charge by applying an electric field.

cathode

The negatively charged electrode in an electrochemical cell or electrophoresis setup where reduction occurs. In gel electrophoresis, DNA fragments migrate towards the cathode.

Electrode

a conductor through which electricity enters or leaves an object, substance, or region.

buffer

A solution that maintains a stable pH in electrophoresis, allowing for optimal separation of DNA fragments during the process.

DNA

The molecule that carries genetic information in living organisms, composed of nucleotide sequences that form genes.

Genes

Segments of DNA that contain the instructions for building proteins and determining traits in organisms.

RNA

RNA (ribonucleic acid) is a molecule similar to DNA that plays a crucial role in coding, decoding, regulating, and expressing genes. Unlike DNA, RNA is typically single-stranded and contains ribose sugar and the nucleotide uracil instead of thymine.

Differences between RNA and DNA

structure: RNA is usually single-stranded, while DNA is double-stranded. 2. Sugar: RNA contains ribose sugar; DNA contains deoxyribose sugar. 3. Bases: RNA uses uracil instead of thymine, which is found in DNA. 4. Function: RNA plays roles in protein synthesis and gene regulation, whereas DNA stores genetic information.