3.2: Carbohydrates, Lipids and Proteins
Nolan Starczak
3.2.1 Distinguish between
organic and inorganic
compounds.
Compounds containing carbon that are found in living organisms
(except hydrogen carbonates, carbonates and oxides of carbon)
are considered organic.
- This means pretty much anything containing a carbon is an
organic compound, while things like water (H2O) and other
mineral based compounds are considered to be inorganic.
3.2.2 Identify amino acids, glucose,
ribose and fatty acids from diagrams
showing their structure.
In this section you will have to be able to identify and draw the
generalized structures of an amino acid and a fatty acid. Also you
will need to be able to identify and draw both glucose and ribose.
See pictures of all at the bottom.
3.2.3 List three examples each of
monosaccharides, disaccharides and
polysaccharides.
-Monosaccharides are the smallest of the carbohydrates and are
considered a sugar, they serve as fuel for the bodies cells. Three
examples of a monosaccharide are glucose, galactose and fructose.
-Disaccharides are formed by two monosaccharides covalently
bonding to each other in a dehydration reaction. Three examples
of disaccharides are maltose, lactose and sucrose.
-Polysaccharides consist of up to thousands of monosaccharides
joined together by glycosidic linkages. Polysaccharides serve as
storage material or cellular building structures. Three examples of
a polysaccharide are starch, glycogen and cellulose
3.2.4 State one function of glucose,
lactose and glycogen in animals, and
of fructose, sucrose and cellulose in
plants.
-Glucose is an essential in animal cells since it is the cells main
source of energy. Since lactose contains the monosaccharide
glucose in it, lactose can be broken down in order to obtain
glucose. This is only done if little glucose is present since it is not
as efficient. Animals store sugar for short term use in the form in
glycogen. Glycogen molecules are stored mainly in muscle and
liver cells.
-Fructose is equivalent of glucose in plants in that it is the main
carbohydrate found in plants, main use in monosaccharide form is
energy. Plants generally transport carbohydrates throughout their
structure in the form of sucrose. Energy is stored within plants in
the form of starch, usually in the form of amylase.
3.2.5 Outline the role of condensation
and hydrolysis in the relationships
between monosaccharides,
disaccharides and polysaccharides;
between fatty acids, glycerol and
triglycerides; and between amino
acids and polypeptides.
These monomers are connected and broken apart with the aid of
dehydration and condensation reactions. In a dehydration reaction
two monomers are bonded when a hydroxyl group (-OH) and a
hydrogen (-O) are removed. These two groups are removed and
form water and the two monomers bind together at the same site.
A hydrolysis reaction is the basically the reverse of a dehydration
reaction. Bonds between monomers are broken with an addition of
water molecules to each. A picture of this can be seen at the
bottom.
3.2.6 State three functions of lipids.
-Lipids can be used for long term energy storage in the form of
fat. One gram of fat contains more then twice as much energy that
is in a gram of starch.
-Phospholipids can be used to make due to the ambivalence of the
phospholipids head and tails towards water. The heads are
hydrophilic (water loving) and the tails hydrophobic (water
fearing) which allows them to create a water tight membrane.
Picture of this can be seen at the bottom.
-Lipids are also structural components in steroids, such as
cholesterol. Sex hormones are steroids produced from cholesterol.
3.2.7 Compare the use of
carbohydrates and lipids in energy
storage.
3.2.2
Glucose
3.2.5
Energy stored in lipids is much more efficient per pound than
carbohydrates. Because plants are virtually immobile than can
cope with the bulkier energy storage of carbohydrates like starch.
Animals on the other hand use lipids for energy storage due to the
fact it is more advantageous to have a compact energy which
allows them more movement. Energy is also much more readily
available in the form of carbohydrates than it is with lipids.
Ribose
3.2.6
3.2 Key Vocab Terms: -Carbohydrate
-Lipid
-Protein
-Organic Compound
-Monosaccharide
-Disaccharide
-Condensation Reaction
-Hydrolysis Reaction
-Inorganic Compound
-Polysaccharide