3.2 Carbohydrates, Lipids And Proteins Flashcards
Distinguish between organic and inorganic compounds
Organic compounds are compounds which are found in living organisms and contain carbon. Inorganic compounds are those which do not contain carbon.
State three compounds which fit the definition of organic compounds, but are classified as inorganic
Carbonates, hydrogen carbonates and oxides of carbon.
State three kinds of organic compounds
Carbohydrates, lipids, proteins.
State three kinds of inorganic compounds
Minerals, metals, salts.
Outline the structure of ribose
Pentose sugar. Five carbons, four in a ring.
Outline the structure of glucose
Hexose sugar. Six carbons, five in a ring.
Outline the structure of an amino acid
Central carbon + hydrogen + amino group + carboxyl group + variable ‘R’ group.
Outline the structure of fatty acids
Carboxyl group + long hydrocarbon chain. Chain length ranges from 4-30 carbons.
List three monosaccharides
Glucose, Galactose, Fructose.
List three disaccharides
Lactose, Maltose, Sucrose.
List three polysaccharides
Starch, Glycogen, Cellulose.
Outline the function of glucose
Source of energy which can be broken down to form ATP via cell respiration.
Outline the function of lactose
Sugar found in milk, provides energy for young mammals.
Outline the function of glycogen
Used for short term energy storage (between meals), stored in muscles and liver.
Outline the function of fructose
Make fruit sweet, attracts animals who eat fruit and spread seeds.
Outline the function of sucrose
Transportable energy form for plants, transported in solution.
Outline the function of cellulose
Main component of cell wall, makes plants strong.
Outline condensation
Molecules are covalently joined together, water is formed as a by-product. In carbohydrates, the bonds is a glycosidic bond. The reaction is brought about by an enzyme.
Outline hydrolysis
A water molecule splits the covalent bond between two molecule. Reverse of condensation; chains of carbohydrates broken down into their smaller components. Brought about by an enzyme (different from condensation).
State three functions of lipids
Buoyancy
-Lipids are less dense than water, helping animals to float.
Insulation
-Fats in animals can serve as heat insulators.
Storage of energy
-Triglycerides can be used for long-term energy storage.
Compare the energy storage of carbohydrates and lipids
Lipids have more energy per unit mass than from carbohydrates.
Compare the solubility of carbohydrates and lipids
Lipids are insoluble, while sugars are highly soluble.
Compare the ease of breakdown of carbohydrates and lipids
Lipids are not easily digested, while carbohydrates are quickly hydrolysed, and thus the transferring energy is quicker.
