Nucleic Acids: The Strands that Bind!

Nucleic Acids: The Strands that Bind!

by Chris Tindle

​Nucleic Acid Basics

Nucleic acids, and DNA in particular, are key macromolecules for the continuity of life.

​

DNA bears the hereditary information that’s passed on from parents to children, providing instructions for how (and when) to make the many proteins needed to build and maintain functioning cells, tissues, and organisms.

​Nucleic Acid Monomers

Nucleic acids have monomers just like other macromolecules we have talked about.

​These monomers are known as nucleotides and they have 3 parts to them:

​

​Phosphate Group

​Sugar molecule

​Nitrogen Base

Multiple Choice

Review Time: What is the name of the bond that binds together monomers of proteins?

• Dehydration Reaction

• Ester Bond/Linkage

• Peptide Bond

• Glycosidic Bond/Linkage

Multiple Select

Review Time: What are the two most common monomers of carbohydrates? Hint: On example is Glucose and the other is Fructose

Multiple Answers expected here

• Pentose Sugars

• Hexose Sugars 

• Triose Sugars

• Octaose Sugars

• M

Multiple Choice

What is the monomer of nucleic acids?

• Nucleotides

• Amino Acids

• Monosaccharides

• Fatty Acids Head and Fatty Acid Tails

​Two types of Nucleic Acids

Nucleic acids, macromolecules made out of units called nucleotides, come in two naturally occurring varieties: 

​

Deoxyribonucleic acid (DNA) and 

Ribonucleic acid (RNA).

​

DNA is the genetic material found in living organisms, all the way from single-celled bacteria to multicellular mammals like you and me. Some viruses use RNA, not DNA, as their genetic material, but aren’t technically considered to be alive (since they cannot reproduce without help from a host).​

Multiple Choice

True or False: DNA is single stranded while RNA is double stranded

• True 

• False

​Details on RNA

​While there are any different types of RNA produced by the cell, the big three I want to focus on are:

​

​mRNA (messenger RNA)

​tRNA (transfer RNA)

​and rRNA (Ribosomal RNA)

​

​Each with a very important role that relates to another Nucleic acid, DNA!

​The roles of each type of RNA

​Taking it from the top:

​mRNA: Specifically, messenger RNA (mRNA) carries the protein blueprint from a cell's DNA to its ribosomes, which are the "machines" that drive protein synthesis.

​rRNA: Ribosomal RNA (rRNA) associates with a set of proteins to form ribosomes. These complex structures, which physically move along an mRNA molecule, work with tRNA to string together various proteins.

​tRNA: Transfer ribonucleic acid (tRNA) is a type of RNA molecule that helps decode a messenger RNA (mRNA) sequence into a protein. tRNAs function at specific sites in the ribosome during translation, which is a process that synthesizes a protein from an mRNA molecule.

Multiple Select

What are the 3 types of RNA discussed in the previous slides?

Multiple Answers expected here

• rRNA

• tRNA

• mRNA

• miRNA

• siRNA

Multiple Choice

True or False: mRNA contains the "message" that is used to code for proteins

• True

• False

Multiple Choice

True or False: A mistake in the gene sequence of DNA can cause a mistake in the proteins being made from said sequence.

• True 

• False

​Nucleotide Bases

The nitrogenous bases of nucleotides are organic (carbon-based) molecules made up of nitrogen-containing ring structures. 

Each nucleotide in DNA contains one of four possible nitrogenous bases: adenine (A), guanine (G) cytosine (C), and thymine (T).

​

RNA nucleotides may also bear adenine, guanine and cytosine bases, but instead of thymine they have another nitrogen base called uracil (U).

​DNA as Code

​It's important to think about DNA as the biological code of Life. Life as we know it would not exist without DNA.

​

​While DNA itself is important enough, I want to cast a specific focus on the Nitrogenous bases discussed in the last slide.

Multiple Select

What are the 4 nitrogen bases associated with DNA?

Multiple Answers expected here.

• Adenine (A)

• Thymine (T)

• Uracil (U)

• Guanine (G)

• Cytosine (C)

Multiple Select

What are the 4 nitrogen bases associated with RNA?

Multiple Answers expected here. 

• Guanine (G)

• Cytosine (C)

• Thymine (T)

• Uracil (U)

• Adenine (A)

​Comparing DNA and RNA

​DNA and RNA are not too dissimilar from one another

​

​Pause