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Clinical Obesity
overweight to a degree which causes medical complications
Triglycerides are formed by condensation from three fatty acids and one glycerol.
KEY CONCEPT:
What is a Triglyceride ?
Triglycerides are a kind of fat (lipid). They are located inside the blood. Upon consumption the body converts the calories which are unneccessary into trigylcerides. They are stored in the form of fat cells.
Subsequent to this, hormones emit triglycerides for the purpose of energy (this occurs between periods of consumption.
In conclusion, if the value of calories consumed exceeds the value of the calories burnt, (especially carbohydrates and fats) there will be a high quantity of tryglycerides ; this is known as hypertriglyceridemia)
What is a glycerol?
Glycerolipids are composed of glycerol and fatty acids. Glycerol consists of three carbon atoms, each each of the three carbon atoms is bound to a hydroxyl (-OH) group. (Figure 1)
Triglyceride Animation
Figure 1: "Glycerol"
Condensation reaction of glycerol video
What are Steroids?
Similar structure of four fused rings in their molecule.
Examples of Steroid include: Chlosterol, progesterone, estrogen and testosterone. (figure 2)
Lipids are glycerol. They are glycerol which is a combination of 1 to 3 fatty acids.
Following this logic, triglycerides are referred to as lipids.
What are phospholipids?
Similar to triglycerides HOWEVER; they acquire two fatty acids (instead of three) whcih are connected to glycerol
Instead of a third fatty acid, they have a phosphate group.
KEY POINT: Phospholipids are partially hydrophobic ( water hating) and they make up the foundation of membranes.
Figure 2 : Steroid examples
In the animation to the right, 3 molecules of fatty acid (stearic acid) combine with 1 molecule of glycerol. Following this, 3 water molecules (blue) are removed.
The carboxylic and glycerol acids acquire -OH bonds. Collaboratively these provide 2 hydrogen atoms in addition to 1 oxygen atom, in order to create the water.
Subsequent to this, three ester linkages (in green) are created.
The compound (glyceryl tristearate - C57H110O6!) which is created afterwards, is also referred to as a trigylceride. The molecule acquires many carbon atoms which are linked to hydrogen atoms; in the form of hydrocarbons and not in the form of -OH groups.
It is due to THIS that fats don't dissolve in water.
As there is a large quantity of C-C in addition to C-H bonds, lipids also attain an increased energy storage capability.
in lipids the condensation reaction does not continue more than what has been outlined, as here are only 3 sites for fatty acids for the glycerol to be attached to .
Condensation reaction: worked example
Phospholipid diagram
