Difference between Primary Metabolites and Secondary Metabolites

Metabolites refer to the immediate products of metabolic activities. These are catalysed by the enzymes in our body to carry out specific functions. Because there are multiple processes in our body, these metabolites are classified into two broad categories - primary and secondary.

Herein, you have to study about the difference between primary and secondary metabolites and their functions. Both are small molecules in our body and essential in performing various internal processes. So, make sure you study every detail of both primary metabolites and secondary metabolites to ace NEET with high grades.

Definition of Primary Metabolites

The fundamental metabolic functions induced by the body enzymes result in the formation of primary metabolites. In turn, these help in carrying out functions like the growth of cells in your body. Furthermore, these metabolites also aid in the maintenance of cellular activities. 

While answering what are primary metabolites, students must note that these are the ones providing the primary metabolic functions. In simple words, these are directly involved in processes such as reproduction, in the form of lactic acid. 

Other forms of primary metabolites include carbohydrates, lipids, proteins, etc. Notably, it is proven that these are highly essential for the body growth of an individual. They directly induce energy into the cells and help in their growth.

 Besides, these are also helpful in the reproduction process, as already mentioned earlier. All of this together makes the primary metabolites an integral part of the growth phase of a living being. 

So, while you are studying for NEET, make sure you go through the primary metabolites notes for a clear understanding especially since these are also vital for other related topics.

Meaning of Secondary Metabolites 

Secondary metabolites are by-products of primary metabolites. Naturally, these are not directly involved in carrying out bodily functions such as cellular growth and maintenance of the same. As a result, they do not form the part of central metabolites either.

Thus, when you study what are secondary metabolites, ensure you are aware of primary metabolites. As the name implies, the secondary comes after there have performed the primary functions in the body. 

Please note, when the growth phase has ended and there is the stationary phase, the secondary metabolites are into function. Other than this, these metabolites are also utilised in multiple external purposes.

Alkaloids and phenolics are of no use to the body and are only useful when they are processed or mixed with other agents. Students should also note here, these secondary metabolites are found mostly in plants. However, a comparison will help in better understanding of the same. Let us look at the table in the next section.

To help you develop a stronghold on the difference between primary and secondary metabolites here is a tabular representation of the major points. Make sure you study them in detail and understand each point.

Comparison between Primary and Secondary Metabolites

Sl. No. 

Basis of difference

Primary Metabolites

Secondary Metabolites


The immediate end products produced by a living organism as a result of growth are called primary metabolites.

The metabolites that help in carrying out other bodily functions which are not involved in the growth and maintenance of cellular activities are called secondary metabolites.

Another name

The other name is trophophase.

Another name is idiophase.  

Area of occurrence

It occurs during the growth phase of an organism.

It occurs during the stationary phase of an organism. 


These metabolites are uniformly produced in almost every species during their growth period.

These metabolites are not produced in a similar manner in every species. They vary for different species. 


Besides the growth of cell, reproduction, these metabolites are also used in various industrial purposes. These are mainly acids that find multiple applications in various manufacturing units or factories. 

These are secondary in nature; however they are used as antibiotics and gibberellins. Besides, though they are not directly involved in cell growth, they act as supporters. They ensure that cell growth continues for a longer duration. 


The primary metabolites include amino acid, lactic acid, vitamins, carbohydrates, lipids, etc. 

Steroids, alkaloids, essential oils, phenolic, etc. are a few examples of secondary metabolites.

So, you can see from the above table that both primary and secondary metabolites are essential for the overall survival of a living organism. While the former helps in the initial stages of growth, the latter helps in sustaining it for a longer period of time. 

How to Crack NEET with the Smartest Preparation

Acing NEET is a dream for all medical aspirants in the nation. To achieve that, all you have to do is focus on every topic included in the syllabus. Revise the difference between primary and secondary metabolites thoroughly along with other topics for gaining an upper hand.

Also, go through the primary and secondary metabolites ppt and try to note down the relevant points for your future reference. Remember, hard work coupled with smart work plays a vital role in acing such a high standard nationwide competitive entrance exams.

So, here is wishing you the best for your exam!

FAQ (Frequently Asked Questions)

1. What do you mean by primary metabolites?

Ans. The primary metabolites are the immediate products of metabolic activities that take place during growth phase of an individual. It also supports the overall development of a body by performing the fundamental physiological functionalities.

2. What is meant by secondary metabolites?

Ans. As the name implies, secondary metabolites are the immediate by-products of primary metabolites. They are produced in the stationary phase, after the growth phase is over.

3. What are some examples of primary and secondary metabolites?

Ans. Some examples of primary metabolites are lactic acid, amino acids, vitamins, lipids, carbohydrates, proteins, etc. Examples of secondary metabolites are alkaloids, steroids, phenolics, essential oils, etc.

4. Which are the applications of secondary metabolites?

Ans. Secondary metabolites are used in various manufacturing units such as pigments, flavourings, medicinal drugs, antibiotics, immunosuppressant, anti-ageing medications, antiviral drugs, etc.