Quiz

• Main organic substances present in food

  • Carbohydrates
  • Fats
  • Protein
  • Nucleic acids
• Carbohydrates


  One of the main components of our diet, the major source of energy for the body, contains simple sugar, starch and cellulose, has carbon, hydrogen and oxygen
• Types of carbohydrates


  • Monosaccharides
  • Disaccharides
  • Polysaccharides
  • Oligosaccharides
• Monosaccharides


  The simplest carbohydrates, very soluble in water, the basic sub unit of carbohydrates, include glucose, galactose and fructose
• Disaccharides


  Carbohydrates that yield two monosaccharide molecules, provide a quick source of energy, include sucrose, lactose and maltose
• Polysaccharides


  Large molecules made up of many smaller monosaccharide units joined together, include starch, cellulose and glycogen
• Oligosaccharides


  Molecules formed by linking together a small number (typically 3-10) of monosaccharides, play important roles in cell recognition, cell adhesion, and signaling
• Lipids are organic compounds that are nonpolar molecules, soluble only in nonpolar solvents and insoluble in water
• Lipids


  Molecules that can be synthesized in the liver, found in oil, butter, whole milk, cheese, fried foods, and some red meats
• Lipids


  • Store energy for later use
  • Found in hormones and cell membrane components
  • Include carboxylic acid/fatty acids and triglycerides/neutral fats
• Fats


  Solids at room temperature, contain saturated fatty acids
• Oils


  Liquids at room temperature, contain unsaturated fatty acids
• Steroids


  Class of lipids with fused ring molecules, most important is cholesterol
• Excessive levels of cholesterol in the blood can lead to deposits in the arteries, a leading cause of heart disease
• Fats have a higher concentration of calories compared to carbohydrates and protein
• Functions of lipids


  • Long-term storage of chemical energy
  • Insulation
  • Organ cushioning
  • Waterproofing
• Types of proteins


  • Complete proteins (meat, fish, seafood, eggs, soy)
  • Incomplete proteins (nuts, grains, fruits, vegetables)
• Proteins


  The most functionally diverse biomolecules, found in all living cells, required for growth and maintenance of the body, composed of amino acids joined by peptide bonds
• Protein structures


  • Primary structure
  • Secondary structure
  • Tertiary structure
  • Quaternary structure
• Primary structure


  The polypeptide chain, the sequence and length of amino acids
• Secondary structure


  The coiling of the protein chain into alpha-helix, beta-sheets, or random structures
• Tertiary structure


  The overall 3D shape of the coiled and folded polypeptide chain
• Quaternary structure


  The clustering of several individual peptides into a final specific shape
• Denaturation is when the shape of a protein is altered, causing it to lose its functionality