Nucleotides and Nucleic Acids Flashcards
What is a nucleic acid?
Polymers that are made up of many repeating units (monomers) called nucleotides.
What 3 components make up a nucleotide?
- A PENTOSE SUGAR
- A NITROGEN-CONTAINING ORGANIC BASE
- A PHOSPHATE GROUP
What are the components of a DNA nucleotide?
- A DEOXYRIBOSE SUGAR with hydrogen at the 2’ position
- A phosphate group
- One of four nitrogenous bases - ACGT
What are the components of an RNA nucleotide?
- A RIBOSE SUGAR with a hydroxyl (OH) group at the 2’ position
- A phosphate group
- One of four nitrogenous bases - ACGU
What does the presence of the hydroxyl group in RNA do?
It makes RNA more susceptible to hydrolysis.
What is the difference between a purine and a pyrimidine?
Purines have a double ring structure whereas pyrimidines have a single ring structure.
What are the purines?
Adenine and Guanine.
What are the pyrimidines?
Thymine, Uracil and Cytosine.
What type of nucleotide is ATP?
A phosphorylated nucleotide.
What does ATP do?
- USED TO TRANSFER ENERGY
- It is the energy-carrying molecule that provides the energy to drive many processes inside living cells.
What do animals specifically require energy for? (ATP)
- Muscle contraction
- Conduction of nerve impulses.
What do ALL organisms require energy for? (ATP)
- ANABOLIC reactions
- Moving substances
What are the 2 stages of protein synthesis?
Transcription and translation
What is the 1st stage of protein synthesis?
Transcription
What happens during transcription?
A molecule of mRNA is made in the nucleus.
What happens during translation?
Amino acids join together to form a polypeptide chain.
What happens during the first stage of transcription?
The hydrogen bonds between the complementary bases break and the DNA uncoils, thus separating the two strands.
What happens during the second stage of transcription?
One of the DNA strands is used as a template by RNA polymerase to make the mRNA molecule. (The DNA template is called the antisense strand)
