D’Arcy, C. J., and Domier, L. L. 2000. Barley Yellow Dwarf. The Plant Health Instructor. DOI: 10.1094/PHI-I-2000-1103-01
Gergerich, R. C., and Dolja, V. V. 2006. Introduction to Plant Viruses, the Invisible Foe. The Plant Health Instructor. DOI: 10.1094/PHI-I-2006-0414-01
Gonsalves, D. S., Tripathi, J. B. Carr, and Suzuki, J. Y. 2010. Papaya Ringspot Virus. The Plant Health Instructor. DOI: 10.1094/PHI-I-2010-1004-01
National Research Council. 2012. A Framework for K–12 Science Education: Practices, Crosscutting Concepts, and Core Ideas. Committee on a Conceptual Framework for New K–12 Science Education Standards. Board on Science Education, Division of Behavioral and Social Sciences and Education. The National Academies Press, Washington, DC.
Riley, M. B., Williamson, M. R., and Maloy, O. 2002. Plant Disease Diagnosis. The Plant Health Instructor. DOI: 10.1094/PHI-I-2002-1021-01
Scholthof, K-B. G. 2000. Tobacco Mosaic Virus: The Beginning of Plant Virology. The Plant Health Instructor. DOI: 10.1094/PHI-I-2000-1010-01
Capsid. The hollow protein cage that encloses a virus particle.
DNA. The abbreviation of “deoxyribonucleic acid,” an organic compound found in all prokaryotic and eukaryotic cells and in some viruses. DNA carries the genetic information of inherited traits.
Enzyme. A biological molecule essential to all the chemical transformations that sustain life.
Families and genera. Families and genera are two categories or groups in the hierarchical system used to classify biological organisms. A “family” is a subgroup of an order, while a “genus” (plural: “genera”) is subgroup of a family. The purpose of this system is to categorize organisms into groups that share similar morphological, chemical, physiological, ecological, and molecular characteristics.
Genome. The complete set of genetic material present in an organism; consists of either DNA or RNA. The genome contains the information needed to complete the organism’s life cycle.
Nucleic acid. A natural polymer (a large molecule composed of many subunits) that enables the reproduction of organisms. There are two types of nucleic acids: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA provides instructions for its own replication, and RNA is synthesized from a DNA template. In turn, RNA controls protein synthesis. Proteins are essential for all cellular functions.
RNA. The abbreviation of “ribonucleic acid,” a string of nucleotides that functions in cellular protein synthesis and replaces DNA as a carrier of genetic codes in some viruses.
Sense. Refers to the molecular polarity of the nucleic acid (RNA or DNA). Depending on the sense of the RNA, a virus uses different mechanisms to reproduce. Positive-sense viral RNA is directly translated by the host cell, while negative-sense viral RNA must first be converted to positive RNA and then translated.
Transcription. Transcription is the synthesis of RNA from a DNA template. A segment of DNA is read by an enzyme and produces RNA.
Translation. Translation is the genetic process through which a protein is produced from RNA template. Translation is the second step in protein manufacturing (following transcription).
Vector. A virus carrier, carrying a virus from one place to another. Insects are the most common vectors of plant viruses, but nematodes, mites, and microorganisms are also possible carriers of plant viruses.