Many people associate metabolism with food and drink, or those complicated diagrams showing thousands of connections. But knowing about metabolism is crucial for understanding life. Biochemists have been fascinated by this subject for over 150 years.

The Goal Of Metabolism

Metabolism aims to map out all the reactions that turn the food we eat into the energy our bodies use, and then into the waste products we expel.

Metabolism Meaning

The term comes from the Greek word “metabolē,” which means ‘to change.’ It includes all the chemical reactions that happen in cells, which are necessary for life.

Types Of Metabolic Reactions

The chemical reactions involve both building up and breaking down complex macromolecules and can be categorized into two processes: catabolism and anabolism. 

Catabolism 

It refers to the breakdown of complex macromolecules (like carbohydrates and proteins) into simpler molecules like carbon dioxide, water, and ammonia. 

Anabolism 

It involves biosynthetic pathways that create complex macromolecules such as nucleic acids, proteins, polysaccharides, and lipids.

Metabolism is structured into specific pathways to either maximize energy capture or minimize energy usage. In catabolism, pathways are arranged so that energy is released slowly in small units. In anabolism, these small units of energy are used to do work, such as building biomolecules.

Heterotrophs And Autotrophs

Organisms are divided into two main categories: heterotrophs and autotrophs. 

Autotrophs

This comes from ‘auto’ meaning ‘self’ and ‘-trophs’ meaning ‘food’. They are the organisms that can make their own food using energy from sunlight and inorganic nutrients from their surroundings. They convert carbon into complex molecules. E.g. plants

Heterotrophs

These include most microorganisms and animal cells, which cannot produce their own food. Instead, they rely on consuming other organisms or their products for energy and growth. E.g. humans

Importance Of Metabolism

Metabolism is crucial for humans because it’s what keeps our bodies functioning properly. 

Here are a few key reasons why it is important:

• Energy production: It converts the food we eat into energy that our bodies can use to carry out various activities, from basic functions like breathing and circulating blood to more active tasks like walking, running, and exercising.

• Nutrient processing: It breaks down carbohydrates, proteins, and fats from our diet into smaller molecules that the body can absorb. The body then uses these nutrients to build and repair tissues, regulate hormones, and support overall health.

• Weight management: It plays a role in determining how efficiently our bodies burn calories. A faster metabolism can help prevent weight gain by burning more calories, while a slower metabolism may lead to weight gain if calorie intake exceeds energy expenditure.
• Waste elimination: It helps eliminate waste products generated during the breakdown of nutrients, such as carbon dioxide and urea. Efficient metabolism ensures that these waste products are removed from the body to maintain proper functioning.

• Regulation of body temperature: As a byproduct of energy metabolism, the body produces heat, which helps regulate body temperature and keeps us warm in colder environments.

Related: 10 Foods That Boost Metabolism

Summary

Metabolism is like a complex factory where all sorts of chemical reactions happen to break down the food you eat into smaller parts that your body can use for energy, growth, and repair. At the same time, it also helps build up the things your body needs, like muscles and bones. 

References

1. Metabolism. Essays Biochem. 2020. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7545035/
2. Physiology, Metabolism. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK546690/