Lipids Flashcards
Name two groups of lipids
Phospholipids
Triglycerides
What type of bond do Saturated fatty acids have?
Single
What type of bond do unsaturated fatty acids have?
Double
Structure of a fatty acid
Long hydrocarbon chain attached to a carboxyl group
Carboxyl group= -COOH
What makes up a triglyceride?
1 glycerol, 3 fatty acids
How to triglycerides form?
During a condensation reaction
3 water molecules are removed
3 ester bonds are formed
Properties of triglycerides
High ration of C-H bonds to carbon atoms in the hydrocarbon chain
Hydrophobic/non-polar
Insoluble in water
How does having a high ratio of C-H bonds to carbon atoms relate to the function of a triglyceride?
good energy store
How does being hydrophobic relate to the function of a triglyceride?
Insoluble in water- clump in droplets
This makes storage easier
doesn’t affect water potential of the cell
What is the difference in structure between a triglyceride and a phospholipid?
One of the fatty acids of a triglyceride is substituted by a phosphate containing group
Properties of phospholipids
Phosphate heads are hydrophilic
Fatty acid tails are hydrophobic
How do hydrophilic phosphate heads relate to the structure of phospholipids?
They are attracted to water so point to the water each side of the membrane, help control the movement of water into the membrane
How do hydrophobic fatty acid tails relate to the structure of phospholipids?
They repel water so face away from the water either side of the membrane
Function of phospholipids
Form a bilayer in the cell membrane which allows the diffusion of lipid soluble (non-polar) or small substances and restricts the movement of water soluble (polar) or larger substances.
Are lipid soluble molecules polar or non-polar?
Non-polar
