1.1 Biological Molecules: Lipids Flashcards
Name the main Structural differences between a phospholipid and a triglyceride.
A phospholipid is made up of a phosphate group attached to a glycerol molecule and two fatty acid tails. In contrast, a triglyceride is made up of one glycerol molecule with three fatty acid tails.
What is the general formula of a fatty acid? What does the term variable group mean?
The general formula is ROOH. The term variable group refers to the hydrocarbon tail, noted as the letter R.
How is a triglyceride formed? What is the name of the bond formed?
For a triglyceride to form three condensation reactions must occur between one glycerol molecule and three fatty acids. This reaction is a condensation reaction where three water molecules are produced and three ester bonds are formed between the fatty acids and the glycerol.
What types of triglycerides are there?
Saturated: which has no double bonds
Unsaturated: which has a double bond and a kink (a bend) in the chain.
Explain how to test for triglyceride.
To test for a triglyceride you would add the sample into a test tube then you would add ethanol shake and then add water and then shake once again after shaking if a white emulsion forms this means a triglyceride is present
What is the main function of triglycerides and phospholipids and how are they suited for these functions?
Fatty acid tails contain a lot of chemical energy (which is released when they are broken down via hydrolysis) more over as triglycerides have three fatty acid tails and phospholipids have two fatty acid tails they all contain a lot of chemical energy. Moreover, due to the fatty acid tails being hydrophobic the molecules are insoluble which means they do not affect the water potential of the cell. The phospholipids having a hydrophilic head and a hydrophobic tail this mean s that they can form a membrane allowing only certain substances to pass through easily those that are water soluble will have it harder due to the hydrophobic centre.
