Carbohydrates and lipids

• Carbohydrates


  Composed of carbon, oxygen and hydrogen, have very different properties due to differences in the form of their molecules
• Lipids


  Composed of carbon, oxygen and hydrogen, have very different properties due to differences in the form of their molecules
• A total of 1679 different molecules with wide range of properties have been identified in watermelon plant

  
• Molecules


  • Raffinose (oligosaccharide)
  • Chitotriose (oligosaccharide)

  
• Raffinose


  An oligosaccharide (trisaccharide composed of galactose, glucose and fructose) that have been extensively used as medicine, cosmetic, and food additives. These dietary fiber fractions avert the adhesion and colonization by enteric pathogens and add nutrition metabolites for a healthy immune system.

  
• Chitotriose


  An oligosaccharide

  
• Carbohydrates as energy storage compounds

  In the form of starch or glycogen
• Lipids as energy storage compounds

  In the form of fats or oils
• Carbohydrates and lipids are chemically stable and energy is released when they are oxidized by cell respiration
• Carbon is only the 15th most abundant element on Earth, but without it, life would not exist
• Covalent bond


  Sharing a pair of electrons between two adjacent atoms, the negatively charged electrons are attracted to the positive charged nuclei of both atoms, these bonds are the strongest type of bonds between atoms
• Carbon atoms


  • Can form four covalent bonds
  • Can form single, double, or triple bonds
• Methane


  Carbon atom bonded with four hydrogen atoms
• Ethanol


  Carbon atom bonded with oxygen and hydrogen
• Carbon compounds


  • Chrysanthemic acid (ring of three carbon atoms that works as a natural insecticide)
• Fatty acids


  Contain unbranched chains of up to 20 carbon atoms
• Macromolecules


  Molecules composed of a very large number of atoms with a relatively molecular mass above 10,000 atomic mass units
• Main classes of macromolecules

  • Polysaccharides
  • Polypeptides
  • Nucleic acids
• Polymer


  Long molecule consisting of many similar or identical building blocks linked by covalent bonds
• Monomer


  Smaller molecules that serve as the building blocks of a polymer

  
• Polymers and their monomers

  • Polycarbohydrates - Monocarbohydrates
  • Proteins - Amino acids
  • DNA - Nucleotides
• Condensation reaction


  1. Two molecules become covalently bonded to each other though the loss of a small molecule, usually water (dehydration reaction)

  2. One molecule provides the hydroxyl group (-OH) and the other the hydrogen (-H)

  3. Facilitated by specialized enzymes

  4. Energy is required, supplied by ATP

  
• Hydrolysis


  1. Chemical process that splits molecules by the addition of water, functioning in disassembly of polymers to monomers

  2. A hydrogen of the water molecule attaches to one monomer and the hydroxyl group to the adjacent monomer

  
• Digestion (hydrolysis of food molecules with the aid of specific enzymes) happens in all cells and outside the cell in the gut of animals. Decomposers release digestive enzymes into the environment to break down polymers by hydrolysis.
• In the human body thousands of different monomers can be found, they might vary from cell to cell. In siblings the variation of DNA and proteins is easily observed.
• The polymers are constructed from only 40 to 50 common monomers and some others that occur rarely, the key is the arrangement.
• Carbohydrates


  Form of carbon, hydrogen, and oxygen, provide energy for cells, their structures are related to their functions
• Monosaccharides


  The simplest carbohydrates, active alone or serving as monomers for disaccharides and polysaccharides, generally have molecular formulas that are multiples of CH2O, have between three and seven carbon atoms

  
• Glucose


  The most common monosaccharide, major nutrient of the cell (for cellular respiration), has a carbonyl group (>C=O) and multiple hydroxyl groups (-OH), is an aldose and a hexose, its carbon skeleton also serves as raw material for the synthesis of other small organic molecules

  
• Fructose


  A structural isomer of glucose, is a ketose and a hexose, present naturally in fruits and vegetables, either as free fructose or as part of the disaccharide sucrose and its polymer insulin

  
• Ribose


  The most important monosaccharide in the life of living organisms after glucose, due to its role in the structure of nucleotides, has five carbons and is present even in the smallest organisms like viruses and bacteria

  
• Glucose


  A useful property for food storage, but causes osmotic problems if stored in large quantities, so it is usually converted to glycogen or starch

  
• Glucose


  Yields energy when oxidized, can be used as a substrate for respiration

  
• Fructose


  A structural isomer of glucose, a ketose rather than an aldose, a hexose

  
• Fructose


  Present naturally in fruits and vegetables, either as free fructose or as part of the disaccharide sucrose and its polymer insulin
• Fructose metabolism


  Referred to as FRUCTOLYSIS

  
• Ribose


  The most important monosaccharide in the life of living organisms after glucose, due to its role in the structure of nucleotides

  
• Ribose


  Present even in the smallest organisms like viruses and bacteria, a pentose sugar (5 carbons)

  
• Ribose


  Can have linear or closed ring structure, present in ATP, ADP, NADH, NADPH, FADH2, and other nucleotides
• Ribose


  Synthesized from glucose and other monosaccharide molecules in living cells by a process known as PENTOSE PHOSPHATE PATHWAY