Micro Exam 1

• 2 or more atoms=molecules
• atoms in a molecule interact through chemical bonds
• covalent bond is when atoms share electrons directly
• hydrophobic (water bad)
• hydrophilic (water good)
• water is a good solvent for hydrophilic molecules
• hydrogen bonding occurs between partially positively charged H atoms and electronegative atoms
• Functions of carbohydrates:

  • energy storage
  • energy source
  • source of carbon
  • component of nucleic acid
• Monosaccharides are simple sugars
• Disaccharides are 2 mono joined by a glycosidic bond
• Polysaccharides are monosaccharide polymers
• lipids are hydrophobic
• fatty acids are linear carbon chains
• Phospholipids, steroids, cholesterols are lipids
• amino acids are joined by a peptide bond and classified by their chemical properties
• Protein Structure:

  • primary is linear
  • secondary is alpha helical or forms beta sheets
  • tertiary involves folding of the secondary into a 3d shape
  • quaternary is the way two or more proteins arrange in a complex
• most proteins are tertiary structures
• DNA is the polymer of nucleotides
• DNA is made up of a phosphate group, a sugar base, and a nucleobase
• phosphodiester bonds give dna polarity
• DNA: ATGC
• DNA structure:

  • double helix
  • 10 base pairs per turn
  • formed major and minor grooves
  • anti parallel
  • complementary base pairing
  • held together by hydrogen bonds
• base pairing suggests how dna is replicated
• RNA: AU-CG
• Rna is structurally distinct from Dna
• RNA shorter in length sequence and single stranded