Summary of lessons so far
Nucleic acids are molecules that consist of nucleotides that direct cellular activities such as cell division and protein synthesis. Each nucleotide consists of a pentose sugar, a nitrogenous base, and a phosphate group. There are two types of nucleic acids: DNA and RNA.
DNA carries the genetic blueprint of the cell and parents pass it on to offspring (in the form of chromosomes). It has a double-helical structure with the two strands running in opposite directions, connected by hydrogen bonds, and complementary to each other.
RNA is single-stranded and is made of a pentose sugar (ribose), a nitrogenous base, and a phosphate group. RNA is involved in protein synthesis and its regulation. Messenger RNA (mRNA) is copied from the DNA, is exported from the nucleus to the cytoplasm, and contains information for the construction of proteins. Ribosomal RNA (rRNA) is a part of the ribosomes at the site of protein synthesis, whereas transfer RNA (tRNA) carries the amino acid to the site of protein synthesis. microRNA regulates the use of mRNA for protein synthesis.
Glossary of Words
Deoxyribonucleic acid (DNA)
double-helical molecule that carries the hereditary information of the cell
Messenger RNA (mRNA)
RNA that carries information from DNA to ribosomes during protein synthesis
biological macromolecule that carries the genetic blueprint of a cell and carries instructions for the functioning of the cell
monomer of nucleic acids; contains a pentose sugar, one or more phosphate groups, and a nitrogenous base
linkage covalent chemical bond that holds together the polynucleotide chains with a phosphate group linking two pentose sugars of neighboring nucleotides
long chain of nucleotides
type of nitrogenous base in DNA and RNA; adenine and guanine are purines
type of nitrogenous base in DNA and RNA; cytosine, thymine, and uracil are pyrimidines
Ribonucleic acid (RNA)
single-stranded, often internally base paired, molecule that is involved in protein synthesis
Ribosomal RNA (rRNA)
RNA that ensures the proper alignment of the mRNA and the ribosomes during protein synthesis and catalyzes the formation of the peptide linkage
process through which messenger RNA forms on a template of DNA
Transfer RNA (tRNA)
RNA that carries activated amino acids to the site of protein synthesis on the ribosome
process through which RNA directs the formation of protein