3.1.5.1 DNA and RNA structure

• DNA (deoxyribonucleic acid)- holds genetic information , controls cell activity
• Structure of a DNA molecule:

  Double helix is made of repeating nucleotides- phosphate group, deoxyribose (pentose sugar), nitrogen bases (thymine, adenine, cytosine, guanine), which make up polynucleotide chains held together by hydrogen bonds between complementary nitrogen bases.
• DNA molecule:

  A) phosphate

  B) P

  C) nitrogen

  D) thymine

  E) adenine

  F) cytosine

  G) guanine

  H) sugar-phosphate

  I) backbone

  J) deoxyribose

  K) pentose

  
• Condensation reactions between two nucleotides forms a phosphodiester bond
• RNA (ribonucleic acid)- forms ribosomes by transferring genetic information from DNA
• Structure of an RNA molecule:

  Single, shorter chain of polynucleotides, ribonucleotides are linked by phosphodiester bonds, nitrogen bases (uracil, adenine, cytosine, guanine)
• RNA molecule:

  A) phosphate

  B) P

  C) nitrogen

  D) uracil

  E) adenine

  F) cytosine

  G) guanine

  H) sugar-phosphate

  I) backbone

  J) pentose

  K) ribose

  
• Differences between DNA and RNA:

  A) DNA

  B) RNA

  C) thymine

  D) adenine

  E) cytosine

  F) guanine

  G) uracil

  H) adenine

  I) cytosine

  J) guanine

  K) deoxyribose

  L) ribose

  M) double

  N) single

  O) helical

  P) non-helical

  Q) long

  R) shorter

  S) DNA