What Elements Make Up Lipids

Edifice Blocks of Lipids: Living organisms are made of biomolecules (biological molecules) that are essential for performing physiological functions: carbohydrates, proteins, lipids, and nucleic acids. These molecules vary in size, structure, properties, and functions in and amidst cells.

By and large, their structures dictate their biological function. If by any run a risk the construction is disrupted or distorted, this could outcome in the harm of the biomolecule itself.

Amongst these four biomolecules, lipids are considered to exist unique every bit they are not defined by the presence of overall structural properties. Lipids are known for their hydrophobic or "water-fearing" properties that are due to the characteristics of their edifice blocks: glycerol and fat acids.

In this article, explore the building blocks of lipids too as how they are grouped together in order to grade a lipid. Let'southward take a closer look.

Table of Contents

Building Blocks of Lipids
Structure of A Lipid
- one. Glycerol
- 2. Fatty Acids
Examples of Lipids
- A. Cholesterol
- B. Triglycerides
- Functions of Lipids
References

Building Blocks of Lipids

Construction of A Lipid

Lipid Structure

Similar any other biomolecules, lipids are made up of building cake monomers. In biochemistry, a monomer refers to a single molecule that when chemically combined with other monomers (can be of the same type or other molecules) tin course larger and different molecules. Basically, monomers are just composed of simple elements.

Unlike the three biomolecules, lipids are not made up of "true" polymers because of their relatively smaller size and non-repeating monomers.
Every bit alluded to earlier, a lipid molecule is composed of a glycerol and (three) fatty acrid sub-units. They are described in the following.

i. Glycerol

Glycerol Chemical Formula

Considered to be a naturally occurring three-carbon alcohol (contains 1 carbon molecule that is bonded to three OH groups), glycerol is a molecule that serves as the structural backbone of a lipid. Bated from that, glycerol is also used to store energy.

Because of its OH group, glycerol can exist considered every bit a "polyol ", a type of booze that contains more than one OH grouping. Because of this holding, glycerol tin be readily dissolved in water.
Additionally, the presence of these OH groups contributes to the hygroscopic property of glycerol. In other words, it can readily take up and retain water molecules.
In layman'south term, glycerol is as well known as glycerin or glycerine. In industries, glycerol is used as sweeteners and humectants.

2. Fat Acids

Fatty Acids Chemical Formula — Fatty Acids Chemic Formula (Image Source: Wikimedia)

Fatty acids are chains of hydrocarbons that accept diverse lengths and levels of unsaturation that end with carboxylic acid functional groups. The biochemical name of a fatty acid originates from the proper noun of its parent hydrocarbon, with the final "e" being changed to "oic" and adding "acid" in the end.

In biological systems, most fat acids accept an even number of carbon atoms, usually ranging from fourteen to 24, with 16 and 18 carbon atoms being the almost mutual. In animals, the hydrocarbon concatenation is always unbranched.
The biochemical properties of fatty acids and their lipid derivatives are dependent mostly on the length of their chains and levels of saturation. As compared with their saturated counterparts (of the same length), unsaturated fatty acids tend to have lower melting points.
In addition to this, the length of the chain besides affects melting point because shorter chain lengths somehow bear upon the level of saturation and contribute to their fluidity.
As compared with glycerol, fatty acids, being "fats" supply a relatively college amount of energy per gram and accept more biological roles than glycerol.

Fatty Acids Dehydration Process (Image Source: Wikimedia)

And so how are these molecules combined and linked to form a lipid? The OH group found in the glycerol molecule and the carboxyl group of the fatty acids are covalently linked via an ester linkage. dehydration synthesis is needed in order to create this.

Examples of Lipids

There are actually quite a number of examples of lipids in biological systems. Below y'all can find the two most common and naturally occurring ones: cholesterol and triglycerides.

A. Cholesterol

Cholesterol Chemical Structure — (Image Source: Wikimedia)

With a molecular formula of C₂₇H₄₅OH, yous can run into that the lipid derivative cholesterol is made upward of iii parts: a hydrocarbon tail, a hydroxyl group, and 4 hydrocarbon rings. Because of these structures (having fat soluble and water soluble regions, cholesterol is considered to be an amphipathic molecule.

In living organisms, cholesterol serves every bit an important component of the cell membranesouth that enable the torso to biochemically absorb fats and other fat derivatives like vitamins. Aside from that, cholesterol is used to synthesize vitamin D and hormones (i.east. cortisol, testosterone, and estrogen).
While the body can naturally synthesize its ain sources of cholesterol, it still needs to obtain it from other sources similar food. Both synthesized and dietary cholesterol is transported in the torso using lipoprotein molecules.
Cholesterol is a blazon of lipid derivative that is based on steroids.

B. Triglycerides

Triglyceride Chemical Formula — (Prototype Source: Wikimedia)

On the other mitt, triglycerides are lipid derivatives that are derived by and large from glycerol. And every bit their name suggests, they are composed of three molecules of glycerols. Because most lipids are insoluble in h2o, they needed to be transported along with other molecules like proteins during circulation in the body.

In animals, triglycerides are synthesized in the intestines and liver from fatty acid units. Contained in the fat cells, triglycerides are broken down into smaller units to provide the body with energy.
To avoid toxicity and other harms, fatty acids are transported as triglycerides, and molecules like lipoproteins play a huge part in this process (i.eastward., transporting lipids to the peripheral tissues from the liver and back).

Bated from those above two, other examples of lipid derivatives include vitamins (those fatty solubles i such as vitamins A, D, E, and Thou), and waxes. Fats, both the saturated (with single bonds) and unsaturated (with double bonds) ones, are likewise considered as lipid derivatives.

Functions of Lipids

Being nonpolar and hydrophobic as they are, lipids serve as strategic components of the plasma membrane and other cellular constituents like the nuclear membrane and envelope, endoplasmic reticulum (ER), Golgi body, lysosomes, and vesicles.

Interestingly, the composition of these organelles mentioned above varies significantly, therefore suggesting that dissimilar types of lipids are needed for various biological functions.
Like carbohydrates, lipids are also used for the storage of energy. However, the former is only used for immediate purposes while the latter serve for the long term.
Furthermore, lipids also serve of import roles in maintaining the structural integrity of organisms as well as exhibiting functions during cell signaling.

While a lot of people apply the term "fats" for lipids interchangeably, it is of import to note that the former is merely actually a subgroup of the latter. Considering of this notion, lipids are given the idea of having a negative role in wellness.

Despite their functions as mentioned earlier and biological importance, lipids have not been well researched as compared with the remaining biomolecules. The reason behind this is pretty simple: scientists and researchers call back that fats are too complicated to work with (their nature and physiology), and the apparent lack of techniques in order to observe and visualize the levels of lipids.

All the same, the contempo advances and discoveries about the identification, structural backdrop, and biophysics of lipids suggest that this subject has a lot more to testify, thus encouraging broader exploration of these molecules.

Cite This Page

References

Biomolecules – Accessed Nov 28, 2017. PDF
"Structure and Function of Lipids – Video & Lesson Transcript | Study.com". Accessed November 28, 2017. Link.
"Fatty Acids Are Key Constituents of Lipids – Biochemistry – NCBI Bookshelf". Accessed November 28, 2017. Link.
"Overview of Cholesterol and Lipid Disorders – Hormonal and Metabolic Disorders – MSD Manual Consumer Version". Accessed November 28, 2017. Link.