UPSC Essentials brings to you its initiative of subject-wise quizzes. These quizzes are designed to help you revise some of the most important topics from the static part of the syllabus. Attempt today’s subject quiz on Science and Technology to check your progress. 🚨 Click Here to read the UPSC Essentials magazine for May 2025. Share your views and suggestions in the comment box or at manas.srivastava@indianexpress.com🚨 QUESTION 1 With reference to the CRISPR (clustered regularly interspaced short palindromic repeats), consider the following statements: 1. It is an immune system found in microbes such as bacteria which fights invading viruses. 2. When a virus infects a bacterial cell, CRISPR helps to establish a memory in the form of antibodies, like in humans. 3. Base editing is a new version of the CRISPR-Cas9 technology. How many of the statements given above are correct? (a) Only one (b) Only two (c) All three (d) None Explanation — A nine-month-old child born with a rare genetic disease has become the first (known) person to successfully get personalised gene-editing treatment, according to a paper published on May 15 in the New England Journal of Medicine. — To treat him, scientists and doctors from the University of Pennsylvania and the Children’s Hospital of Philadelphia developed a personalised treatment based on “base editing”, a new version of the decade-old CRISPR-Cas9 technology. Hence, statement 3 is correct. — Scientists believe this method has the potential to treat thousands of unusual genetic illnesses. However, there are significant obstacles to its widespread acceptance. What is CRISPR? — After being infected with a virus, individuals develop an "immune memory" in the form of antibodies. When they are infected with the same virus again, these antibodies readily recognise and neutralise the pathogens. — CRISPR, an immunological mechanism found in microbes such as bacteria that fights invading viruses, stands for "clustered regularly interspaced short palindromic repeats". When a virus infects a bacterial cell, CRISPR contributes to the establishment of a memory — but one that is genetic rather than in the form of antibodies, as in humans. Hence, statement 1 is correct and statement 2 is not correct. — When a virus infects a bacterial cell, the bacterium removes a portion of the virus's genome and inserts it into its own genome. CRISPR then creates a new "guide" RNA using the freshly acquired DNA. — During a subsequent attack by the same virus, the guide RNA immediately detects and attaches to virus DNA. The guide RNA then instructs an enzyme (a type of protein) called Cas9 to serve as "molecular scissors" to cut and remove the virus DNA. Therefore, option (b) is the correct answer. QUESTION 2 With reference to the Tianwen-2 mission, consider the following statements: 1. This mission will be launched by Japan, being its first mission to survey and sample a near-Earth asteroid. 2. It will investigate an asteroid called 469219 Kamo‘oalewa, which orbits the Sun at a distance relatively close to Earth. Which of the statements given above is/are correct? (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2 Explanation — China will launch its first mission to survey and sample a near-Earth asteroid this week. Known as the Tianwen-2 mission, the probe will investigate an asteroid called 469219 Kamo‘oalewa, which orbits the Sun at a distance relatively close to Earth. Hence, statement 1 is not correct and statement 2 is correct. — If the mission is successful, China will join a small group of countries, including the United States and Japan, that have successfully sampled and returned asteroids to Earth. — Kamo'oalewa was found in 2016 by the Pan-STARRS 1 asteroid survey telescope on Haleakalā, Hawaii. It is one of only seven asteroids classified as quasi-satellites of Earth, which are satellites that circle the Sun but are gravitationally impacted by the planet due to their proximity. Therefore, option (b) is the correct answer. QUESTION 3 Consider the following statements: Statement 1: When the leaves from trees near a volcano turn greener, it is indicative of the fact that it is active and is about to erupt soon. Statement 2: Greener trees detect early signs of an active volcano by tracing the volcanic carbon dioxide (CO₂). Which one of the following is correct in respect of the above statements? (a) Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1. (b) Both Statement 1 and Statement 2 are correct and Statement 2 is not the correct explanation for Statement 1. (c) Statement 1 is correct but Statement 2 is incorrect. (d) Statement 1 is incorrect but Statement 2 is correct. Explanation — NASA has created a new method of observing volcano patterns by tracking tree health using satellite photos. In collaboration with the Smithsonian Institution's AVUELO (Airborne Validation Unified Experiment: Land to Ocean), space agency experts say they can detect early signals of volcanic eruptions by analysing the changing colours of tree leaves. — The scientists discovered that when the leaves of trees surrounding a volcano turn greener, it indicates that the volcano is active and may erupt soon. Tracing the CO₂ consumption patterns of nearby trees can help detect early indicators of an active volcano. Hence, statements 1 and 2 are correct. — Research indicates that rising magma beneath Earth's surface emits CO₂ and SO₂ into the atmosphere. While detecting sulphur dioxide in the atmosphere is relatively simple, scientists suggest that traces of volcanically produced carbon dioxide are far more difficult to identify. CO₂ can be difficult to identify from other gases in the atmosphere. Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation for Statement 1. Therefore, option (a) is the correct answer. QUESTION 4 Rocket propulsion relies on: 1. Newton's first law of motion 2. Newton's third law of motion. 3. Archimedes' Principle Select the correct answer using the codes given below: (a) 1 only (b) 2 only (c) 1 and 2 only (d) 2 and 3 only Explanation — Ballistic missiles are still used today, but they are far more complex. A ballistic missile is one that is only powered during the initial stages of its flight. After that, it follows a parabolic course, much like a pebble tossed into the air, but quicker and farther. — A typical intercontinental ballistic missile (ICBM) may reach altitudes of more than 1,000 kilometres and speeds of Mach 20 (20 times the speed of sound). Once launched, they are virtually impossible to intercept. But pure ballistic routes are predictable — which is both their strength and weakness. — Guided missiles are equipped with sensors (such as radar, infrared, or GPS) and control systems (gyroscopes, fins, and internal thrusters) that allow them to direct themselves while in flight. — Rocket propulsion follows Newton's Third Law, which states that for every action, there is an equal and opposite reaction. The rocket moves ahead as it burns fuel and expels petrol from the back. The major problem isn't only travelling fast; it's also regulating flight at high speeds. Therefore, option (b) is the correct answer. QUESTION 5 With reference to the planet Uranus, consider the following statements: 1. It is pale blue-green in colour because its atmosphere absorbs the red wavelengths of sunlight. 2. As per the study, Uranus’ atmosphere is primarily composed of hydrogen and helium, along with small amounts of methane. 3. Uranus’ axis of rotation is nearly parallel to its orbital plane. How many of the statements given above are correct? (a) Only one (b) only two (c) All three (d) None Explanation — Uranus, the seventh planet from the Sun, owes its pale blue-green colour to its atmosphere that absorbs the red wavelengths of sunlight, according to a new study. Hence, statement 1 is correct. — The Hubble photos of Uranus were obtained between 2002 and 2022. According to the study, Uranus' atmosphere is mostly made of hydrogen and helium, with trace amounts of methane, water, and ammonia. Hence, statement 2 is correct. — Uranus is situated between Saturn and Neptune. Uranus, the seventh planet from the Sun, is one of the least studied planets in our solar system, which is why the latest research study could be significant. Scientists who wrote the paper also supplied additional information regarding seasonal changes on the planet. Unlike other planets, Uranus' axis of rotation is almost parallel to its orbital plane. Hence, statement 3 is correct. Therefore, option (c) is the correct answer. Correction in May (2025 )Issue of Magazine - Quiz Compilation Question 41 Functions and powers of the United Nations Security Council Correct answer (c) Question 42 F-1 Visas Correct answer (b) Question 41 (This question number has been marked twice) Recently, an original painting from the 1600s, Mary Magdalene in Ecstasy, was unveiled at Delhi’s Italian Cultural Centre. Which famous artist created this work? Correct answer (b) Question 43 Question on Nixon Shock Correct answer (d) Sorry for the inconvenience caused. All remaining questions and answers are correctly marked. Previous Daily Subject-Wise-Quiz Daily Subject-wise quiz — History, Culture, and Social Issues (Week 112) Daily subject-wise quiz — Polity and Governance (Week 112) Daily subject-wise quiz — Science and Technology (Week 111) Daily subject-wise quiz — Economy (Week 111) Daily subject-wise quiz — Environment and Geography (Week 111) Daily subject-wise quiz – International Relations (Week 111) Subscribe to our UPSC newsletter and stay updated with the news cues from the past week. Stay updated with the latest UPSC articles by joining our Telegram channel – IndianExpress UPSC Hub, and follow us on Instagram and X.