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

Monosaccharide Disaccharide Polysaccharide

Animal Example Plant Example

Glucose Lactose Glycogen

Function

Energy source in animal cellular respiration Fructose Energy source. Makes flower nectar sweeter to attract bees Sucrose Energy source. The main carbohydrate in milk Energy source. Transport molecule in the phloem Energy storage molecule in the liver 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 H 2 0 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.

Contain 2 times more energy/gram than carbohydrates Stored as glycogen in liver cells 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