Background Teaching Resources for Genetics and DNA


There are many Technical Terms used in this Field.

To help in learning the material, I have put in a glossary for many of the Biology Terms we use.


One of the four bases in DNA that make up the letters ATGC, adenine is the "A". The others are guanine, cytosine, and thymine. Adenine always pairs with thymine.  Adenine is a purine. 



Base Pair:





Three bases in a DNA or RNA sequence which specify a single amino acid.


One of the four bases in DNA that make up the letters ATGC, cytosine is the "C". The others are adenine, guanine, and thymine. Cytosine always pairs with guanine.  Cytosine is a pyrimidine.


Deoxyribonucleic Acid: The chemical inside the nucleus of a cell that carries the genetic instructions for making living organisms.

DNA Replication


Genetic Code




Gene Pool





The genetic identity of an individual with respect to a particular gene is determined by which specific alleles they received from their parents.  . 


One of the four bases in DNA that make up the letters ATGC, guanine is the "G". The others are adenine, cytosine, and thymine. Guanine always pairs with cytosine.  Guanine is a purine.

Hardy Weinberg Equilibrium

The Hardy–Weinberg principle states that the genotype frequencies in a large, randomly mating population remain constant (in equilibrium) from generation to generation.  Hardy Weinberg Equilibrium can be disrupted with big changes in the genotype frequencies if there is natural selection, small populations, or migration of new individuals into the population.


Base pairing of two single strands of DNA or RNA.

Junk DNA

Non-coding repetitive DNA dispersed throughout the genome.


The place on a chromosome where a specific gene is located, a kind of address for the gene. The plural is "loci," not "locuses."

The energy producing organelle in the cytoplasm.  The mitochondria have small circular chromosomes made of DNA which can differ from person to person.

Non-coding DNA

The strand of DNA that does not carry the information necessary to make a protein. The non-coding strand is the mirror image of the coding strand and is also known as the antisense strand.


The central cell structure that contains the chromosomes.



PCR (Polymerase Chain Reaction)

A fast, inexpensive technique for making an unlimited number of copies of any piece of DNA. Sometimes called "molecular photocopying," PCR has had an immense impact on biology and medicine, especially genetic research.


A short oligonucleotide sequence used in a polymerase chain reaction to start specific DNA replication.  A primer must be the mirror image of the DNA and have a free 3’ end to build new DNA onto.


A piece of labeled DNA or RNA or an antibody used to detect the presence of a gene or protein.




A substance used in a chemical reaction to detect, measure, examine, or produce other substances. Many chemical companies refer to chemicals as "reagent grade" meaning they are of suitable purity to use in experiments. The materials made for an experiment (solutions, enzyme mixtures) can be referred to as reagents as well as purchased materials..

Restriction Enzymes


RFLP (Restriction Fragment Length Polymorphism)


Ribonucleic Acid


Southern Blot

A technique used to identify and locate DNA sequences which are complementary to another piece of DNA called a probe.

STR (Short Tandem Repeat)
STRs are locations on a chromosome that contain short sequences that repeat themselves within the DNA molecule.   The number of repeats can be determined by amplifying the DNA using specific sequences or primers located to the left and right of the repeating region.


One of the four bases in DNA that make up the letters ATGC, Thymine is the "T". The others are adenine, guanine, and cytosine. Thymine always pairs with adenine.

Genetics Tutorials

There are many excellent Genetics Tutorials. One of my favorites comes from the Dolan DNA Learning Center and is called DNA from the Beginning
