Chapter 3 Flashcards
Where are the hydrogen base pairs for A and T and C and G? Also be able to draw the molecules
A and T have 2 Hydrogen base pairs and C and G have 3 Hydrogen base pairs
What is the general structure of a nucleotide?
a sugar (deoxyribose), one of four bases (Cytosine, Thymine, Adenine, Guanine), and a phosphate.
What is Chargaff’s Rule?
states that A = T, C = G
What is the nucleic acid structure?
long chainlike molecules composed of a series of nearly identical building blocks called nucleotides
What is a Phosphodiester linkage?
the linkage between the 3’ carbon atom of one sugar molecule and the 5’ carbon atom of another
What is 5-Bromouracil?
Incorporated into DNA in place of T. It can base pair with G, and the result is change of A-T pair to G-C pair (called transition). 5BrU is commonly used as a form of chemotherapy. Causes massive mutations.
What is mutagenesis?
the process by which an organism’s deoxyribonucleic acids (DNA) change, resulting in a gene mutation
What are the steps of mutagenesis?
Use a synthetic oligonucleotide primer and the gene to be altered. The primer will incorporate the desired base changes recombined to the DNA containing the gene to be altered. PCR reactions insert the alternative mismatches (mismatched nucleotides and primer). DNA polymerase extends the mismatched primer to generate a mutated gene.
How can mutagenesis occur naturally and on a farm?
It can naturally occur with things like UV light and by selective breeding on a farm.
What are DNA restriction enzymes and what do they produce?
recognize a specific sequence of nucleotides in double-stranded DNA and cut the DNA at a specific location, producing DNA fragments with a known sequence at each end
How are restriction enzymes used in biotechnology?
used to splice and insert segments of DNA into other segments of DNA, thereby providing a means to modify DNA and construct new forms
How does the size of a DNA fragment effect how it is ran through a gel?
small fragments move through the gel faster than large ones
What is gel electrophoresis?
a technique used to separate DNA fragments according to their size
How do you read a gel electrophoresis?
Smaller molecules migrate through the gel more quickly and therefore travel further than larger fragments that migrate more slowly and therefore will travel a shorter distance. The gel is read from bottom to top, with smaller fragments on the bottom and bigger fragments on the top.
