c) Cellulose (structural molecule). Used by plants to build their cell walls. Main component of dietary fiber.
LIPIDS (Fats) Lipids make a very varied family of molecules. Found in oils, waxes & fats.
Structure: Glycerol molecule & up to three fatty acids (saturated or unsaturated) bonded together.
One glycerol molecule and up to three fatty acids (saturated or unsaturated)
SATURATED FAT Structural formula of a saturated fat molecule Stearic acid, a saturated fatty acid
Structural formula of an unsaturated fat molecule Oleic acid, an unsaturated fatty acid double bond causes bending UNSATURATED FAT
Unsaturated fats are found in plant products (olive oil, sunflower oil, margarine, avocado...). A healthier diet choice. Saturated fats are found in animal products (bacon, butter, lard...). A less healthier diet choice (exception: fish).
Function: long-term energy storage in the form of triglycerides.
PROTEINS Proteins are found everywhere in the body. They account for 50% of a cell’s dry mass, have a huge range of functions and make up an extremely important group of molecules. Found in meat, eggs, milk, cheese...
29 Proteins consists of many amino acids bonded together.
MANY, MANY DIFFERENT FUNCTIONS! 1. Build structures: organs, blood vessels, muscles, nails, hair (ex: keratin, collagen, actin & myosin). 2. Defence against infection: antibodies are proteins. 3. Transport proteins carry materials around the body (ex: hemoglobin carries oxygen). 4. Chemical control: enzymes are proteins. 5. Body control: hormones are proteins. 6. Buffer proteins prevent pH changes.
NUCLEIC ACIDS (DNA & RNA) Big, massive and immovable DNA is an instruction manual for building an organism. RNA is an assistant molecule necessary for the use of DNA. DNA is used to make chromosomes (46 in humans). Chromosomes are divided into genes (approx. 25000 in humans). Genes store coded information used to build proteins (1 gene=1 protein).