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A nucleic acid is a large biopolymer consisting of many nucleotides. The two primary nucleic acids found in cells are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). What are the functions of these two nucleic acids?
A nucleotide is a molecule that contains a five-carbon sugar, a phosphate group, and a nitrogen containing base. What is the difference between ribose and deoxyribose? (Hint: use the following structures to help you explains)
Note: there is a carbon (C) where the structure bends, and hydrogen atoms are attached to each point, unless otherwise noted (i.e. O and OH).
RNA and DNA both can have adenine, cytosine, and guanine as bases. What bases are unique to each kind of nucleic acid?
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DNA and RNA
A DNA nucleotide looks as follows (specifically adenine, in this case):
DNA and RNA polymers consist of multiple nucleotides strung together into long chains, with only the nitrogenous base changing.
DNA has a double helix shape, with each nitrogenous base on one strand paired up with another base on the opposite strand.
Remember: in DNA, adenine (A) and thymine (T) pair up, while the cytosine (C) pairs with guanine (G). In RNA, uracil (U) replaces thymine!
The following diagram is of a strand of DNA:
How many hydrogen bonds are there in the A-T pairing? In the C-G pairing? What do the 3' and 5' represent?
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Protein synthesis basically consists of DNA producing an RNA template that directs animo acids to be introduced into a protein chain.
First, there's transcription, which is the unfolding or unzipping of the double-stranded DNA and the production of messenger-RNA, or mRNA; the DNA strand uncoils, providing the pattern for the formation of the single-stranded mRNA. What happens to the mRNA afterwards? Where does transcription take place in a cell?
Then, during translation, amino acids will link with specific transfer-RNA, or tRNA, molecules for proper placement in the protein chain. What is the function of tRNA? How do tRNA and mRNA interact? Where does this amino acid assembly occur?
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Each organism contains protein molecules that are specific to that organism, and the base sequence of DNA is responsible for the production of the different proteins present in all living things. How does this work?
A gene is a segment of DNA that carries a code for making specific polypeptide chains. The genetic code works as a series of three-letter codes, or a triplet. How does the gene code relate to amino acids? What triplets act as end or termination codes?
The particular DNA sequence of a certain organism is like a genetic blueprint of that organism. Where is this found? What is the Human Genome Project, and why is it important?
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