RNA (noun, “R-N-A”)
This is short for ribonucleic (Rye-bo-nu-CLAY-ic) acid. RNA is a molecule that helps cells carry out the instructions in DNA. These instructions are found in sections of DNA called genes. They tell cells how to make proteins. Proteins are molecules that carry out important cell functions like converting food to energy and fighting infection.
Both DNA and RNA are made up of building blocks called nucleotides (NU-klee-oh-tydz). The order of these nucleotides in a gene makes up a code. This code tells the body’s cells what kinds of proteins to make. That’s where RNA comes in. Inside a cell’s nucleus, one type of RNA copies the information in the DNA code. This RNA, called messenger RNA, travels to a structure called a ribosome (RYE-bo-zome). The ribosome itself is made up of RNA called ribosomal RNA, which helps “read” the code in the messenger RNA. This code tells another type of RNA, called transfer RNA, to bring the pieces needed to make the proteins to the ribosome. It’s important that the RNA exactly copy the information in the DNA code. If it makes a mistake, the cell might not make the correct protein. In some cases, this can cause serious illness or other harmful effects.
Scientists are still learning about different types of RNA and their roles in the body. Some RNA can turn genes off and on and make modifications to proteins. Others may be bad actors that help tumors spread.
In a sentence
The genetic code in some viruses, like measles and influenza, is made of RNA, not DNA.