1.2 Carbohydrates - Simple Sugars Flashcards
What are carbohydrates?
Carbohydrates are an important source of energy, and it acts as a ‘protein sparer’, so that protein can be used for its primary functions rather than as a source of energy.
What is a name for one of carbohydrates functions to do with protein?
‘Protein Sparer’
What are the three elements carbohydrates contain?
Carbon, oxygen and hydrogen. These are the elements that form all the different types of carbohydrates (CHO).
What are the two simple sugars and their units?
Monosaccharides (single unit) and disaccharides (double unit of two joined monosaccharides)
What are the types of monosaccharides?
Glucose, fructose and galactose
What are the types of disaccharides and what are their double units?
Maltose (glucose + glucose)
Sucrose (glucose + fructose)
Lactose (glucose + galactose)
What are monosaccharides?
Monosaccharides consist of a single sugar molecule and are the simplest carbohydrates, your body can not break them down further. This allows your body to absorb them quickly and easily, with the exception of fructose.
Glucose structure:
Glucose contains 6 carbon atoms and has a specific arrangement of hydroxyl (OH) groups around the carbon atoms in the ring structure, which determine its chemistry.
What is a hydroxyl group?
A hydroxyl group is a functional group consisting of an oxygen atom bonded to a hydrogen atom (OH).
Galactose structure:
Galactose has 6 carbon atoms and its molecule structure is similar to glucoses structure, however it has a different arrangement of hydroxyl groups at the fourth carbon atom.
Fructose structure:
Fructose contains six carbon atoms and a ketone group.
What is a ketone group?
A ketone group is a functional group which has a carbon atom bonded to an oxygen atom by a double bond.
Examples of glucose foods:
Honey
Dried fruits
Examples of fructose foods:
Pear
Watermelon
Examples of galactose foods:
Dairy products
Avocados
Monosaccharide summary:
While glucose, galactose, and fructose all belong to the same family of monosaccharides and share some similarities in their chemical formulas, they differ in their specific molecular structures. These structural differences contribute to variations in their biological functions, metabolic pathways, and physiological effects within the body.
Disaccharide summary:
Disaccharides cannot be absorbed in the small intestine (they are too big) and must be broken down first.
Where are monosaccharides absorbed?
Quickly and easily through the small intestine into the blood.
Where are disaccharides absorbed and what do they have to do first?
Disaccharides must be broken down into monosaccharides before they can be absorbed in the small intestine.
How are disaccharides broken down into their monosaccharides?
They are broken down by a specific enzyme (protein).
How do complications occur?
Some people can’t produce enough of the required enzyme needed to break down disaccharides resulting in complications.
Example of someone not producing the required enzyme:
Individuals who can not produce enough of the enzyme lactase cannot break the lactose in milk down into its two monosaccharides.
Enzyme required for Lactose, Maltose and Sucrose to be broken down into monosaccharides.
Lactose - lactase
Maltose - maltase
Sucrose - sucrase
