DNA Unit

Deoxyribose nucleic acid (DNA) is referred to as the building blocks of life. This arrangement of sugars and phosphate groups looks very much like a twisted ladder. DNA is held together by chemical bonds which determine the genotype (the genetic make-up) and phenotype (physical properties) of an organism. Although DNA is formed by chemical bonding, DNA is central to biology and life for most organisms. The following activities provide bridges between environmental science, biology, and chemistry concepts, reinforcing the connectivity between science disciplines.

Lesson 1

Students will explore various aspects of genetics, including the molecular structure of DNA and genetic changes caused by environmental toxins. This lesson features a transformed research article, Arsenic – The Silent Toxin That Keeps on Giving. The transformed article is based on a research article about how arsenic in drinking water affects epigenetics. Epigenetics is the study of how behaviors and environmental conditions change how our genes work. Unlike mutations, epigenetic changes do not change the DNA sequence. Instead, it changes how the body reads the DNA sequence, primarily affecting when gene are activated or not activated. In other words, changing when genes are turned on and off. These “mis-readings” can impact offspring, making them susceptible to metabolic diseases, such as type 2 diabetes (T2D), later in life.