Unit D - Digestion and Human Health (p.1-13)

• What is nutrition?

  The process of taking and assimilating nutrients; the branch of science concerned with this process.
• What are nutrients?

  A substance that provides nourishment essential for life ad growth.
• What are macromolecules?

  Macromolecules are large, complex organic made up of smaller subunits called monomers, and they include carbohydrates, lipids, proteins, and nucleic acids <- (these are macronutrients).
• What are the micronutrients? What are they called?

  Vitamins and minerals. Micronutrients.
• Are macronutrients organic or inorganic molecules?

  Macronutrients are organic molecules.
• Are micronutrients organic or inorganic?

  Micronutrients are inorganic molecules.
• What are macromolecules made up of?

  Macromolecules are made up of smaller subunits that are assembled by linking together the subunits through covalent bonds between them.
• What is Assembling Macromolecules/ Dehydration Synthesis?

  Assembling Macromolecules/ Dehydration Synthesis is Dehydration (the removal of water).

  A molecule of water is removed by taking the -OH (hydroxyl) group of one subunit and a -H (hydrogen) atom from another subunit. This leaves the subunits bonded together.
• What is Disassembling Macromolecules/ Hydrolysis Reaction?

  Disassembling Macromolecules/ Hydrolysis Reaction is when hydrogen is added.

  A molecule of water is added to the bonds between subunits.

  Breaking apart the subunits.
• What is the primary function of carbohydrates?

  Energy. Carbohydrates are the most important energy source in our bodies. It provides short-term and long-term energy storage.
• What are three simple sugars and where will you find them?

  Glucose, fructose, galactose. Found in fruits, honey, and dairy products.
• What are the components of Sucrose and it's source?

  Components: Glucose + fructose.

  Source: Sugarcane and sugar beets.
• What are the components of Maltose and it's source? Components: Glucose + Glucose Source: Found in germinating grains, such as barley.
• What are the components of Lactose and it's source? Components: Glucose + Galactose Source: Milk and dairy
• What happens to carbohydrates that are not immediately used by your body?

  Carbohydrates that are not immediately used by your body are needed for energy or stored as glycolysis in the liver, which may be converted into fat.
• Why might you want to limit your carbohydrate intake?

  Too much carbohydrates may lead to high insulin levels and cause weight gain.
• How are starch and cellulose alike?

  They are both polysaccharides.
• How are starch and cellulose different?

  They both have different structures and you can digest starch but not cellulose.
• What are fats?

  Fats are lipids. Fats are usually greasy and saturated.
• What are the two structural components of fats?

  Glycerol and (3) fatty acids.
• Why are fats essential to your diet?

  Fats are your body's insulin from the cold, a cushion for many organs, a carrier of Vitamins A, D, E, and K, and a major component of cell membranes and many hormones.
• What do simple (carbohydrate) sugars contain?

  1 carbon: 2 hydrogen: 1 oxygen
• What suffix are sugars often identified by?

  -ose suffix
• When do plants manufacture carbohydrates?

  During photosynthesis
• What are monosaccharides? How many carbons do they contain?

  Monosaccharides are simple sugars. They contain 3 to 6 carbons.
• What are disaccharides?

  Two monosaccharides form a disaccharide.
• What are three disaccharide sugars?

  Sucrose, lactose, maltose.
• Disaccharides are formed by which process?

  Disaccharides are formed by dehydration synthesis.
• What are polysaccharides?

  Carbohydrates formed by more than 2 monosaccharides are called polysaccharides.
• How are polysaccharides formed?

  Polysaccharides are formed by dehydration synthesis.
• What are the two polysaccharides?

  Starch and cellulose.
• What is starch?

  Starch is a polysaccharide that is stored in animals in the form of glycogen and acts as energy storage in plants.
• How many glucose units is starch made up of?

  Starch is made up of 16 to 24 glucose units.
• How is glucose joined for starch?

  The glucoses are joined by dehydration synthesis.
• What happen to excess glucose when making starch?

  Excess glucose are converted into glycogen by insulin and stored in liver and muscles.
• What happens if glucose concentration in the blood decreases?

  If glucose concentration in the blood decreases, glycogen can be converted back into glucose.
• What is cellulose?

  Cellulose is a polysaccharide that makes up the cell walls of plant cells.

  Cellulose is made up of thousands of glucose units combined by dehydration synthesis in long chains.
• True or False; Cellulose is the least abundant carbohydrate in nature.

  False; Cellulose is the most abundant carbohydrate in nature.
• Can cellulose be digested and used for food by humans?

  No, but it is an important source of fibre or roughage in our diet.
• In benedict tests, what colour does blue reagent turn if exposed to heat if sugars are present?

  Orange/Red.