What is the difference between lipids and fats

Most common lipids are found in food in the form of triacyglycerol, cholesterol, and phospholipids and play an important part in having a good health. Withdrawal of lipids can cause the body and weaken and person to fall sick. Fats have become synonymous with lipids, but they are a sub-group of lipids and are known as triglycerides.

Fats are the fatty acid esters of glycerol and are the primary energy depots of animals. The energy depots are used for storing energy that may be required by the body during deprivation of food. Fats are generally soluble in organic solvents and insoluble in water. Fats can be found in solid state as well as liquid state at room temperature; solid state is known as fats, while liquid state is referred to fat at liquid state. Fats differ from some lipids in chemical structure and in physical properties and play an important part in chemical and metabolic functions.

Fats and lipids are broken down in a human body by enzymes called lipases, which are produced in the pancreas. Human bodies also have an adipose tissue, which is known as a fat depot and is a loose connective tissue composed of adipocytes. The main role of this tissue is to store energy in the form of lipids. An excess of this tissue causes obesity in humans. Fats can be categorized into saturated fats and unsaturated fats.

Figure 1: Phospholipid Bilayer. Steroids are a type of hydrophobic molecules mostly found as cholesterol and hormones. Cholesterol is the precursor of other types of steroids in the body. Fats refer to an oily substance that occurs in the body under the skin or around the organs.

Since the degree of saturation of fatty acids is high, fats are typically solid at room temperature. The unsaturated fat is known as oils, which are liquids at room temperature. Typically, fats have an animal origin, and oils have a plant origin. The two types of fats are the saturated fat and the trans fat.

Milk products, meat, butter, and cheese are the major sources of dietary saturated fat. The consumption of saturated fat is good for the health since it increases the levels of good cholesterol or the high-density lipoprotein HDL , which lowers the risk of cardiovascular disease.

Figure 2: Food containing Fat. Trans fat is produced by the partial dehydrogenation of liquid vegetable oils. It contains a single, double bond in its structure. Due to the high degree of saturation, trans fats are also solids at room temperature. The consumption of more trans fat is bad for the health since it increases the levels of bad cholesterol in the blood and decreases the levels of good cholesterol.

Lipids: Lipids are a class of organic molecules that are insoluble in water and soluble in organic solvents. Fats: Fats are an oily substance found in the body, under the skin or around the organs. Lipids: Lipids are a diverse group of biomolecules found in the animal body.

Lipids: Triglycerides, phospholipids, and steroids are the three types of lipids. The hydrophilic head groups of the phospholipids face the aqueous solution. The hydrophobic tails are sequestered in the middle of the bilayer. The head is the hydrophilic part, and the tail contains the hydrophobic fatty acids.

In a membrane, a bilayer of phospholipids forms the matrix of the structure, the fatty acid tails of phospholipids face inside, away from water, whereas the phosphate group faces the outside, aqueous side Figure 9.

Phospholipids are responsible for the dynamic nature of the plasma membrane. If a drop of phospholipids is placed in water, it spontaneously forms a structure known as a micelle, where the hydrophilic phosphate heads face the outside and the fatty acids face the interior of this structure.

Unlike the phospholipids and fats discussed earlier, steroids have a fused ring structure. Although they do not resemble the other lipids, they are grouped with them because they are also hydrophobic and insoluble in water.

All steroids have four linked carbon rings and several of them, like cholesterol, have a short tail Figure Many steroids also have the —OH functional group, which puts them in the alcohol classification sterols.

Figure Steroids such as cholesterol and cortisol are composed of four fused hydrocarbon rings. Cholesterol is the most common steroid. Cholesterol is mainly synthesized in the liver and is the precursor to many steroid hormones such as testosterone and estradiol, which are secreted by the gonads and endocrine glands.

It is also the precursor to Vitamin D. Cholesterol is also the precursor of bile salts, which help in the emulsification of fats and their subsequent absorption by cells.

Although cholesterol is often spoken of in negative terms by lay people, it is necessary for proper functioning of the body. It is a component of the plasma membrane of animal cells and is found within the phospholipid bilayer.

Being the outermost structure in animal cells, the plasma membrane is responsible for the transport of materials and cellular recognition and it is involved in cell-to-cell communication. Lipids are a class of macromolecules that are nonpolar and hydrophobic in nature. Major types include fats and oils, waxes, phospholipids, and steroids. Fats are a stored form of energy and are also known as triacylglycerols or triglycerides. Fats are made up of fatty acids and either glycerol or sphingosine.

Fatty acids may be unsaturated or saturated, depending on the presence or absence of double bonds in the hydrocarbon chain. If only single bonds are present, they are known as saturated fatty acids. Unsaturated fatty acids may have one or more double bonds in the hydrocarbon chain.

Phospholipids make up the matrix of membranes. They have a glycerol or sphingosine backbone to which two fatty acid chains and a phosphate-containing group are attached. Steroids are another class of lipids.

Their basic structure has four fused carbon rings. Cholesterol is a type of steroid and is an important constituent of the plasma membrane, where it helps to maintain the fluid nature of the membrane.

It is also the precursor of steroid hormones such as testosterone. Answer the question s below to see how well you understand the topics covered in the previous section.

This short quiz does not count toward your grade in the class, and you can retake it an unlimited number of times. Use this quiz to check your understanding and decide whether to 1 study the previous section further or 2 move on to the next section.

Skip to main content. Module 3: Important Biological Macromolecules. Search for:. Lipids Illustrate different types of lipids and relate their structure to their role in biological systems In this outcome, we will discuss lipids, or fats, and the role they plan in our bodies. Learning Objectives Distinguish between the different kinds of lipids Identify several major functions of lipids. Figure 3. Stearic acid is a common saturated fatty acid. Figure 4.

Oleic acid is a common unsaturated fatty acid. For an additional perspective on lipids, explore this interactive animation.