General about carbohydrates

1. CARBOHYDRATES
 Carbohydrates are made of 3 Elements only:
Carbon, Hydrogen, Oxygen
It is typical of a carbohydrate that it contains
twice as many hydrogen atoms as oxygen
atoms
Ratio of a carbohydrate
C:H:O
1:2:1
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2.  One of the simplest carbohydrates is
GLUCOSE, which is a type of sugar – single
sugar – MONOSACCHARIDE
 Its chemical formula is: C6H12O6
 One can find glucose in basically all living
things.
 Glucose dissolves very easily in water
therefore is very soluble.
 Glucose is present in all your cells and is
the main substance which provides energy.
CARBOHYDRATES
Other single-sugars are fructose and
galactose.
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3.  Many molecules of glucose can join together
to form a multi-sugar or
POLYSACCHARIDE.
 One example of a polysaccharide is
glycogen. Glycogen forms a food storage
substance in many animals.
 Starch which is also a polysaccharide is the
food storage substance usually used by
plants.
CARBOHYDRATES
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4.  Cellulose is also a polysaccharide formed
from long chains of glucose.
 These chains are grouped together to form
very small (microscopic) fibres that are put in
layers to form the cell wall in plant cells.
CARBOHYDRATES
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5.  When glucose molecules join together water
is REMOVED from them.
 This type of chemical reaction is called
CONDENSATION
CARBOHYDRATES
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6.  The opposite can happen for example starch
broken down into glucose.
 For the glucose molecules to be separated
from one another water has to be added.
 This type of reaction is called HYDROLYSIS.
CARBOHYDRATES
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7.  Some carbohydrates are made of two
glucose molecules connected together. The
resulting sugar is maltose.
 We call these double – sugars or
disaccharides.
 Commonly found table sugar is a double-
sugar called sucrose.
CARBOHYDRATES
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8.  One can get carbohydrates from most foods, but
sweets, chocolates, bread and pasta are very
rich in carbohydrates.
 Starch can be found in bread, potatoes, cereals
and many other foods coming from plants.
CARBOHYDRATES
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