DNA Structure Flashcards
What is a nucleotide
A monomer that joins together to make the polymer of DNA(a nuclei acid)
What is a nucleotide made up
Phosphate bonded to sugar bonded to a base
Bond between phosphate group and sugar in nucleotide and which atoms from which one
Ester bond forms with H from phosphate and OH from sugar, water produced as waste product
Bond between sugar and base in nucleotides and which atoms from which
Glycosidic bond forms with OH from sugar and H from base, water as waste product
What are the four bases and which are complementary
Adenine and thymine, cytosine and guanine
Differences between RNA and DNA
-RNA is one strand
-in RNA thymine is replaced by uracil
-DNA has deoxyribose sugar while RNA has ribose sugar
Structure of DNA
-double helix with the two polynucleotide strands twisted around each other
-phosphate backbone
-long chain polymer made up of monomers called nucleotides(mononucleotides)
How are the bases held together
Hydrogen bonds
Number of hydrogen bonds formed between adenine and thymine
2 hydrogen bonds
Number of hydrogen bonds formed between cytosine and guanine
3 hydrogen bonds
Bond that forms between nucleotides and which molecules does it form between
Phosphodiester bond, forms by condensation reaction between sugar of one nucleotide and phosphate of the next one
What is a gene
A sequence of bases on a DNA molecule that codes for a sequence of amino acids in a polypeptide chain
