Module 2 - Nucleotides and nucleic acids Flashcards
Give two examples of nucleic acids
RNA and DNA
What three components make up a nucleotide?
- a phosphate group
- a pentose sugar
- an organic base
What purines are found in DNA and RNA?
adenine and guanine
What pyrimidines are found in DNA?
cytosine and thymine
What pyrimidines are found in RNA?
cytosine and uracil
What is the difference between purines and pyrimidines?
purines are two carbon rings whilst pyrimidines are one carbon ring
What type of nucleotides are RNA and DNA?
polynucleotide
What is the structure of RNA?
- single-stranded and short
- sugar involved is ribose
- base is ACGU
What are the three types of RNA?
- messenger RNA - mRNA
- tranfser RNA - tRNA
- ribosomal RNA - rRNA
What is mRNA?
- carries the code held in the genes to the ribosomes where the code is used to make proteins
What is tRNA?
- transports amino acids to the ribosomes
What is rRNA?
- makes up the ribosome
What does C bond to in DNA, what type of bond, and how many bonds?
Guanine, 3 hydrogen bonds
What does A bond to in DNA, what type of bond, and how many?
Thymine, 2 hydrogen bonds
Describe the structure of the DNA strands
- antiparallel meaning they lie in opposite directions
- the two strands combine and twist to make a double helix
Explain how the nucleotides in a DNA molecule are arranged as two polynucleotide strands.
- adjacent nucleotides binding together via a condensation reaction to form phosphodiester bonds
- this creates a sugar-phosphate backbone between the sugar of one molecule and the phosphate group of another
- hydrogen bonds are between complementary base pairings.
- polynucleotides are antiparallel
What are ATP and ADP?
- phosphorylated nucleotides
What do ATP and ADP contain?
- pentose sugar
- nitrogenous base
- two or three inorganic phosphates