Transcript 3.2 Carbohydrates, lipids annd proteins

3.2.1: Distinguish between organic and inorganic compounds
Organic compounds contain carbon and are found in living things. (Except hydrogen
carbonates, e.g. sodium hydrogen carbonate, carbonates, e.g. calcium carbonate and
oxides of carbon, e.g. carbon dioxide)
3.2: Carbohydrates, lipids and proteins
3.2.1:Carbon compounds in living organisms
• Protein
• Carbohydrate
• Lipid
• Nucleic acid
(D.N.A. R.N.A.)
3.2.1:Contain carbon but not considered carbon compounds in living organisms
*Hydrogencarbonates
E.g. potassium hydrogen
carbonate
*Carbonates
E.g. Sodium carbonate
* Oxides of Carbon
E.g. Carbon dioxide
3.2.2: Identify amino acids, glucose, ribose and fatty acids from diagrams
showing their structure.
3.2.3: List three examples each of monosaccharides, disaccharides and
polysaccharides.
Monosaccharides (from the Greek mono, “single” and sacchar, “sugar”) are the simplest
carbohydrates.
Examples include: 1) glucose, 2) galactose and 3) fructose.
Disaccharides, or double sugars, are assembled when two monosaccharides are joined
by condensation.
Examples include: 1) maltose, 2) lactose and 3) sucrose.
Polysaccharides are polymers comprised of hundreds or thousands of simple sugars.
The sugar monomers are joined by condensation.
Examples include: 1) starch, 2) glycogen and 3) cellulose.
3.2.4: State one function of glucose, lactose and glycogen in animals, and of
fructose, sucrose and cellulose in plants.
Type of sugar
Animal
Example
Plant Example
Function
Energy source in animal cellular
respiration
Glucose
Monosaccharide
Fructose
Energy source. Makes flower nectar
sweeter to attract bees
Energy source. The main
carbohydrate in milk
Lactose
Disaccharide
Sucrose
Glycogen
Energy source. Transport molecule in
the phloem
Energy storage molecule in the liver
Polysaccharide
Cellulose
Forms cell walls in plant cells
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.
Each cell contains thousands of complex molecules called macromolecules.
There are four major classes of macromolecules: Carbohydrates, Lipids, Proteins, and Nucleic
acids.
Cells make their macromolecules by linking many small molecules together end to end, forming
chains called polymers.
A polymer is a large molecule composed of many identical or similar subunits (monomers)
strung together.
Monomers are joined together by the removal of water molecules, a process known as
condensation.
The reverse process, hydrolysis, breaks polymers apart by adding water molecules.
3.2.5:Condensation reaction with Monosaccharide to form di/polysachharide
3.2.5:Hydrolysis reaction with di/polysachharide to form a monosaccharide
3.2.5:Condensation reaction with amino acids to form peptide to polypeptide
3.2.5:Hydrolysis reaction with peptide to form amino acids
3.2.5:Condensation reaction with glycerol and fatty acids to form a triglyceride
3.2.5:Hydrolysis reaction with triglyceride to form glycerol and fatty acids
3.2.5: Condensation/hydrolysis reaction
• Fatty acid and glycerol
3.2.5: Condensation/hydrolysis
reaction
• Fatty acid and glycerol
3.2.5: Condensation/hydrolysis reaction
• Fatty acid and glycerol
+1 H20 molecule
3.2.6 State three functions of Lipids
Phospholipids function to hold cell membranes
together and create a boundary between the cell and
its external environment.
Steroids function as hormones.
Fats function to: 1) cushion vital organs;
2) insulate the body; and
3) store energy.
3.2.7: Compare the use of carbohydrates and lipids in energy storage
Lipids
Carbohydrates
Normally used for long term energy storage.
Normally used for short term energy storage.
Stored as fat in adipose cells.
Stored as glycogen in liver cells
Contain 2 times more energy/gram than
carbohydrates
Contain 2 times less energy per gram than
lipids
Less soluble in water than carbohydrates.
More soluble in water thus easier to transport
in blood