Unit D, Bio 20

• What are the three main categories of food?

  Carbohydrates, lipids, and proteins.
• What are carbohydrates composed of?


  Carbon, hydrogen, and oxygen.
• What is the ratio of elements for carbohydrates?

  1 : 2 : 1
• Glucose


  A carb with the formula C6H₁₂O6.
• What is the main role of carbs?

  To provide energy for the body.
• Where are carbs found?

  In all plant based foods.
• What are the three types of carbohydrates?


  Manosaccharides, Disaccharides, Polysaccharides
• Manosaccharides

  A single sugar unit with 3-8 carbons
• What is unique about monosaccharides?

  They can switch between cyclic and chain forms.
• Isomers


  Carbs with the same chemical formula but arranged in different ways.
• What are examples of monosaccharides?


  Fructose, glucose, galactose
• Disaccharides


  A reducing sugar with two sugar units.
• How are disaccharides formed?

  By monosaccharides linking together.
• How are monosaccharides linked together?

  Through dehydration synthesis, or condensation, which involves the loss of a hydroxide ( OH- ) ion from one monomer, and a hydrogen from another.
• What is the by product of dehydration synthesis?


  H2O
• What is unique about disaccharides?

  They contain over 7 carbon atoms.
• What is sucrose formed from?

  Glucose & fructose
• What is maltose formed from?

  Two glucose molecules
• What is lactose formed from?

  Glucose & galactose
• Polysaccharides


  Complex carbs, or many simple sugars linked together.
• What are examples of polysaccharides?

  Starch & cellulose
• What is unique about cellulose?

  Because it is difficult to break down, it offers little energy but is a source of fibre.
• What are lipids composed of?

  Carbon, hydrogen, and oxygen.
• What are lipids built from?

  Fatty acids, which are arranged atoms.
• What distinguishes lipids from carbs?

  The carboxyl group ( COOH ).
• What does the carboxyl group cause?

  Lipids to be non polar, which is why they repel water and have an oily or waxy consistency.
• What do lipids do?

  Store energy, are a component of our cell membranes, help carry vitamins, and play a role in hormone synthesis.
• Where are lipids found?


  In foods containing animal based fats or plant based oils.
• What is unique about saturated fatty acids?

  Their carbon chain consists of only single bonds.
• What is the structure of saturated fatty acids?

  A rectangular shape which allows chains to pack together easily.
• What are the characteristics of saturated fatty acids?

  Are solid at room temperature, are difficult to break down, and typically from animals.
• How are unsaturated fatty acids classified?


  They have one or more double bonds in their carbon chain which leads to a kinked shape, meaning chains cannot be easily packed together.
• What are characteristics of unsaturated fatty acids?

  Are liquid at room temperature, easy to break down and typically from plants.
• Hydrogenation


  Is used to convert unsaturated fats into saturated fats through the breaking of double bonds and the addition of hydrogen.
• Triglycerides


  The lipids that store energy in our body.
• How are triglycerides formed?

  Through the union of a glycerol molecule, a 3 carbon lipid, and three fatty acids, through the process of dehydration synthesis.
• What are fats?


  Triglycerides solid at room temperature, they tend to be saturated and are derived from animals.
• What are oils?


  Triglycerides liquid at room temperature, they tend to be unsaturated and are derived from plants.
• What do triglycerides do?

  Store energy in the body.
• What is unique about triglycerides?

  They can be broken down into carbohydrates and released into the bloodstream to provide our cells with energy during periods of fasting.