In what ways do variation in form allow diversity of function in carbohydrates and lipids?
How do carbohydrates and lipids compare as energy storage compounds?
Bonds that share the electrons between two atoms.
Bonds where electrons are transferred and charge keeps the atoms together.
All organic molecules contain two or more atoms of carbon. Carbon atoms easily bond to each other and can form four single covalent bonds, or a fewer combination of single and double bonds with other atoms, allowing a diversity of stable compounds to exist.
Life is based on carbon compounds, that seem complex, but are all just made from smaller divisions (monomers), that then link together to form polymers.
Macromolecule (Polymer) | Smallest Unit (Monomer) | Elements |
---|---|---|
Carbohydrate | Monosaccharides | Carbon, hydrogen and oxygen. |
Lipids | Fatty Acids and Glycerol | Carbon, hydrogen and oxygen. |
Proteins | Amino acids | Carbon, hydrogen, oxygen and nitrogen. Other elements are also often present, for example sulphur and phosphorus |
Nucleic acids(DNA & RNA) | Nucleotides | Carbon, hydrogen, oxygen, nitrogen and phosphorus. |
Carbohydrate are produced by linking together monosaccharide monomers to build disaccharide and polysaccharide polymers using a glycosidic bond.
This is a condensation reaction (H2O released)
Form of Carbohydrate | Examples | Use in Plants | Uses in Animals |
---|---|---|---|
Monosaccharide | Fructose Glucose Galactose | Fructose is a component of fruits making them taste sweet and attracting animals to eat them, thereby dispersing the seeds inside | Glucose is the source of energy for cell respiration – it is obtained from the digestion of carbohydrate foods |
Disaccharide | Sucrose Lactose Maltose | Sucrose is transported from leaves to storage tissues and other parts of the plant to provide an energy source | Lactose is found in milk and provides energy for young mammals |
Polysaccharide | Cellulose Starch Glycogen | Cellulose is a structural component of plant cell walls Starch is used a food store | Glycogen is the storage carbohydrate of animals, found in the liver and muscles |