Lipids Flashcards
(17 cards)
Triglycerides at room temperature…
Fats are solid, oils liquid
The name and structure of what triglyceride is based on
H H H
H C C C H
OH OH OH
(A molecule of glycerol)
Joined onto the glycerol molecule for a triglyceride are…
Three fatty acid chains
Where do the fatty acid chains join onto the glycerol molecule?
The OH groups on the glycerol molecule
What reaction occurs when three fatty acid chains join onto the glycerol molecule?
Condensation reaction, producing three water molecules
When are fatty acids saturated?
When they don’t have any C=C double bonds
Saturated fatty acids are…
Straight chains with high melting points
When are fatty acids unsaturated?
When there are C=C double bonds in the hydrocarbon chains (of the fatty acids)
Unsaturated fatty acids are…
Bent chains with low melting points
If the fatty acid chains have more than one C=C double bond, they are called…
Polyunsaturated
What is the difference between a triglyceride and a phospholipid?
While they are both based on one molecule of glycerol, where triglycerides have three fatty acid chains joined, phospholipids have two fatty acids and a phosphate group
Phospholipids can be called…
Polar molecules
What is a polar molecule?
Where the phosphate head of the molecule is hydrophilic (loves water) and the fatty acid tail is hydrophobic (hates water)
When the phospholipids mix with water…
They form droplets where the phosphate heads are in contact with the water, and the fatty acid chains are excluded from it
Phospholipids can form a phospholipid bilayer in water when…
A pocket of water is captured within the double layer of phospholipid molecules, which is seen in cell membranes
What test can be done to observe lipids?
An emulsion test
The emulsion test for lipids…
Add the sample to a clean, grease free test tube, add ethanol, and mix, and water, which will form a cloudy white emulsion/precipitate if there is a lipid present
