UPSC Essentials | Mains answer practice — GS 3 : Questions on biosignatures and protein language models (Week 120)

QUESTION 1

What are protein language models (pLMs)? Discuss how they help in understanding protein structure and function.

QUESTION 2

What are “biosignatures”, and why are they critical in the search for past or present life on Mars?

General points on the structure of the answers

Introduction

— The introduction of the answer is essential and should be restricted to 3-5 lines. Remember, a one-liner is not a standard introduction.

— It may consist of basic information by giving some definitions from the trusted source and authentic facts.

Body

— It is the central part of the answer and one should understand the demand of the question to provide rich content.

— The answer must be preferably written as a mix of points and short paragraphs rather than using long paragraphs or just points.

— Using facts from authentic government sources makes your answer more comprehensive. Analysis is important based on the demand of the question, but do not over analyse.

QUESTION 1: What are protein language models (pLMs)? Discuss how they help in understanding protein structure and function.

Note: This is not a model answer. It only provides you with thought process which you may incorporate into the answers.

Introduction:

— Protein language models trained on evolutionary data have emerged as powerful tools for predictive problems involving protein sequence, structure and function.

— The recent emergence of large language models (LLMs) has revolutionised the research on proteins — the microscopic mechanisms that are involved in virtually every important activity happening inside all living things. Scientists use a version of LLM for various tasks, such as predicting the structure or function of a protein, which contributes to the development of drugs and vaccines.

Body:

You may incorporate some of the following points in your answer:

— The LLMs used for protein research are known as protein language models (pLMs). Unlike the usual LLMs, which are trained on English words, pLMs are trained on protein sequences — the linear, specific order of one-dimensional amino acids that are linked together to form a three-dimensional protein.

— Typically, proteins are made of a combination of 20 different kinds of amino acids, and the structure and function of each protein are governed by the arrangement of the various amino acids in it. For instance, antibody proteins fold into shapes that help them to identify and target foreign bodies, like when a key fits into a lock.

— Protein language models are trained on protein sequences and their objective is to predict the next amino acid in a sequence, just like regular language models which predict the next word in a sequence.

— The pLMs can intuit the patterns and interrelationships between protein sequence, structure and function. They can, for example, infer how changing amino acids in certain locations of a protein sequence could impact the shape that the protein folds into.

— This helps scientists save a lot of time and effort, as earlier, they had to carry out extensive experiments using X-rays, microscopes and other tools to determine the shape and function of proteins.

Conclusion:

— An LLM or pLM can make predictions because it is an artificial neural network. Just as the human brain is composed of neurons that connect and send signals to each other, these artificial neural networks are composed of several interdependent layers of neurons. It is these neurons that process large amounts of data to recognise patterns and make predictions.

(Source: How scientists got a glimpse of the inner workings of protein language models)

Points to Ponder

Read more about protein language models

Related Previous Year Questions

Discuss several ways in which microorganisms can help in meeting the current fuel shortage. (2023)

What is the basic principle behind vaccine development? How do vaccines work? What approaches were adopted by the Indian vaccine manufacturers to produce COVID-19 vaccines? (2022)

QUESTION 2: What are “biosignatures”, and why are they critical in the search for past or present life on Mars?

Note: This is not a model answer. It only provides you with thought process which you may incorporate into the answers.

Introduction:

— The US National Aeronautics and Space Administration (NASA) has found the strongest signs yet that some form of life may have existed on Mars in the past.

— NASA said that its Mars rover Perseverance, which has been roaming the surface of the Red Planet since February 2021, had picked up “potential biosignatures” in a rock sample that it scanned last year.

Body:

You may incorporate some of the following points in your answer:

— A potential biosignature is a substance or structure that might have a biological origin but requires more data or further study before a conclusion can be reached about the absence or presence of life.

— Perseverance, the six-wheel, small car-sized rover had come across a rock – later named Cheyava Falls – on its designated route, which seemed to possess attributes that scientists thought were worth investigating for potential microbial signatures from the past.

— Based on data sent by instruments aboard the rover, scientists determined that certain chemicals and structures on the rock were such that could have been formed by living organisms billions of years ago. NASA revealed this in July 2024, but said that more detailed analysis was required.

— This finding by Perseverance is the closest we have ever come to discovering life on Mars. The identification of a potential biosignature on the Red Planet is a groundbreaking discovery, and one that will advance our understanding of Mars.

— The analysis by the onboard instruments found that the rock sample was composed of clay and silt, and also contained organic carbon, sulphur, oxidised iron (rust), and phosphorus. On Earth, clay and silt are excellent preservers of past microbial life, NASA said in a statement.

Conclusion:

— The Cheyava Falls rock will undergo more detailed analysis. Perseverance had drilled into the rock and acquired a small sample a few centimetres in size – it is one of the 30-odd samples the rover has collected from various locations on Mars so far.

— “The combination of these minerals, which appear to have formed by electron-transfer reactions between the sediment and organic matter, is a potential fingerprint for microbial life, which would use these reactions to produce energy for growth. The minerals also can be generated abiotically, or without the presence of life. Hence, there are ways to produce them without biological reactions,” NASA said.

(Source: Potential biosignatures: Why NASA says we may be closest ever to discovering life on Mars, http://www.nasa.gov)

Points to Ponder

Read more about Mars

Read more about potential biosignatures

Related Previous Year Questions

Launched on 25th December, 2021, James Webb Space Telescope has been much in the news since then. What are its unique features which make it superior to its predecessor Space Telescopes? What are the key goals of this mission? What potential benefits does it hold for the human race? (2022)

What is the main task of India’s third moon mission which could not be achieved in its earlier mission? List the countries that have achieved this task. Introduce the subsystems in the spacecraft launched and explain the role of the Virtual Launch Control Centre’ at the Vikram Sarabhai Space Centre which contributed to the successful launch from Sriharikota. (2023)

Previous Mains Answer Practice

UPSC Essentials: Mains answer practice — GS 3 (Week 118)

UPSC Essentials: Mains answer practice — GS 3 (Week 119)

UPSC Essentials: Mains answer practice — GS 2 (Week 118)

UPSC Essentials: Mains answer practice — GS 2 (Week 119)

UPSC Essentials: Mains answer practice — GS 1 (Week 119)

UPSC Essentials: Mains answer practice — GS 1 (Week 118)

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