Sugars

• What is a monosaccharide?

  A monosaccharide is a single sugar molecule.
• Can you give examples of monosaccharides?

  Examples of monosaccharides include glucose, galactose, and fructose.
• What is the structure of glucose?

  The structure of glucose is a ring shape.
• What is the chemical formula of glucose?

  The chemical formula of glucose is $C_6H_{12}O_6$.
• What elements do all carbohydrates contain?

  All carbohydrates contain carbon, hydrogen, and oxygen.
• How many carbon atoms does glucose contain?

  Glucose contains six carbon atoms.
• What are sugars with six carbon atoms called?

  Sugars with six carbon atoms are called hexose sugars.
• Why do scientists simplify the structure of glucose in diagrams?

  Scientists simplify the structure of glucose to make it easier to understand.
• What is the term for single sugar molecules?

  Single sugar molecules are called monosaccharides.
• What does the prefix "mono" in monosaccharide mean?

  The prefix "mono" means one.
• What is a key feature of monosaccharides regarding solubility?

  Monosaccharides are soluble in water.
• Why are monosaccharides soluble in water?

  Monosaccharides are soluble in water due to the presence of hydroxyl groups.
• What are hydroxyl groups?

  Hydroxyl groups are functional groups consisting of an oxygen atom bonded to a hydrogen atom.
• What term describes molecules that are water-loving?

  Molecules that are water-loving are called hydrophilic.
• What are monosaccharides with five carbon atoms called?

  Monosaccharides with five carbon atoms are called pentose monosaccharides.
• Can you give an example of a pentose monosaccharide?

  An example of a pentose monosaccharide is ribose.
• What can monosaccharides be chemically joined to form?

  Monosaccharides can be chemically joined to form disaccharides and polysaccharides.
• What are the main types of carbohydrates formed from monosaccharides?

  • Disaccharides: Formed from two monosaccharides.
  • Polysaccharides: Formed from multiple monosaccharides.
• What will be covered in the next video regarding carbohydrates?

  The next video will cover disaccharides and polysaccharides.
• What are disaccharides formed from?

  Disaccharides are formed from two monosaccharides.
• What is the difference between alpha and beta glucose?

  Alpha glucose has the hydroxyl group on carbon one pointing below the plane of the ring, while beta glucose has it pointing above.
• What disaccharide is formed when two alpha glucose molecules react together?

  The disaccharide formed is called maltose.
• What is produced alongside the formation of a disaccharide from monosaccharides?

  A molecule of water is produced during the formation of a disaccharide.
• What type of reaction occurs when a water molecule is formed during the formation of a disaccharide?

  This reaction is called a condensation reaction.
• What is a glycosidic bond?

  A glycosidic bond is a new chemical bond formed between two monosaccharides during the formation of a disaccharide.
• Between which carbon atoms does the glycosidic bond form in maltose?

  The glycosidic bond in maltose forms between carbon one of one alpha glucose and carbon four of the other alpha glucose.
• What are the two other disaccharides that need to be learned besides maltose?

  • Sucrose: formed from glucose and fructose
  • Lactose: formed from glucose and galactose
• What happens when water is added to a disaccharide?

  Adding water to a disaccharide breaks the glycosidic bond, converting it back to the original monosaccharides.
• How is the hydrolysis reaction typically carried out in cells?

  This reaction is normally carried out by enzymes in cells.
• What is the significance of learning the diagram of glycosidic bonds in disaccharides?

  • It could be asked to draw in an exam.
  • It helps understand the structure and formation of disaccharides.
• What are the two categories of sugars mentioned in the video?

  Reducing sugars and non-reducing sugars
• What is a reducing sugar?

  A reducing sugar can donate an electron to another molecule
• Which monosaccharide is given as an example of a reducing sugar?

  Glucose
• What are some examples of disaccharides?

  Maltose, lactose, and sucrose
• Which disaccharides are considered reducing sugars?

  Maltose and lactose
• Which disaccharide is a non-reducing sugar?

  Sucrose
• What is the procedure to test for reducing sugars using Benedict's solution?

  1. Grind food with distilled water and filter.
  2. Add 3 cm³ of food solution to a boiling tube.
  3. Add 3 cm³ of Benedict's solution.
  4. Heat in boiling water for 5 minutes.
  5. Observe color change:

  • Blue: no reducing sugar
  • Green: small amount
  • Yellow: moderate amount
  • Orange: higher amount
  • Brick red: large amount
• What does a blue color indicate in the Benedict's test?

  There is no reducing sugar present
• What happens to the copper ion in Benedict's solution when a reducing sugar is present?

  It is reduced from Cu$^{2+}$ to Cu$^{+}$, forming a red precipitate
• Why is the Benedict's test considered semi-quantitative?

  It shows a narrow range of color changes and human color perception varies