Daily subject-wise quiz : Science and Technology MCQs on Zero Shadow Day, tumour marker test and more (Week 110)
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.
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Consider the following statements about Zero Shadow Day:
1. It occurs when the Sun's declination—its angular distance north or south of the celestial equator—matches the latitude of a particular location.
2. It occurs thrice a year in regions situated between the Tropic of Cancer and the Equator
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
— Several regions in West Bengal will witness the rare and scientifically significant phenomena known as Zero Shadow Day (ZSD) this year in June and July.
— This astronomical occurrence occurs twice a year in places between the Tropic of Cancer and the Equator, when the Sun is directly overhead at local noon, allowing objects to cast no shadows for a brief duration. Hence, statement 2 is not correct.
— Zero Shadow Day happens when the Sun's declination (angular distance north or south of the celestial equator) corresponds to the latitude of a certain location. Hence, statement 1 is correct.
— At that same instant, the Sun reaches its greatest position in the sky, straight overhead, casting no visible shadow on upright objects. The effect is most visible for a few minutes at solar noon, when the Sun crosses the local meridian.
Therefore, option (a) is the correct answer.
The monographs (related to upper atmosphere) are the instruments which measure:
1. Pressure
2. Temperature
3. Relative humidity
Select the correct answer using the codes given below:
(a) 1 and 2 only
(b) 2 only
(c) 3 only
(d) 1, 2 and 3
Explanation
— In the wake of budget cuts by the Trump administration, a Silicon Valley startup will soon start to replace the National Oceanic and Atmospheric Administration's (NOAA's) weather balloons with AI-powered alternatives, which are supposed to be much cheaper.
— Weather balloons are used by weather agencies all around the world to collect upper air measurements, which are critical for forecasting. Upper air refers to the Earth's atmosphere above 5,000 feet, from which the globe receives rain and drought, wind and stillness, heat and cold at its surface.
— The practice of making upper-air observations dates back to the 18th century. It all started in 1749, when two students from Glasgow, Scotland, used kites to record temperature at great altitudes. Meteorologists began to deploy kites into the high atmosphere carrying aloft sensors known as monographs, which measured pressure, temperature, and relative humidity.
Therefore, option (d) is the correct answer.
With reference to the microalgae, consider the following statements:
1. They are microscopic algae with high chlorophyll content that lack lignin and cellulose but contain proteins.
2. They are primarily found in freshwater.
3. It can be used to treat industrial wastewater.
4. It can recycle CO2 to O2 while providing nourishment.
How many of the statements given above are correct?
(a) Only one
(b) Only two
(c) Only three
(d) All four
Explanation
— Microalgae are known to grow quicker in microgravity environments and can recycle CO2 to O2 while producing nourishment. Hence, statement 4 is correct.
— Microalgae are microscopic algae with high chlorophyll content that lack lignin and cellulose but contain proteins. Hence, statement 1 is correct.
— Microalgae are primarily found in freshwater and marine ecosystems. Hence, statement 2 is correct.
— Microalgae can be successfully used to treat industrial wastewater. According to the researchers, as the microorganisms feed, they expand and reproduce, offering a wealth of algae-based biomass for the production of bioenergy, high-value bio-based chemicals, and speciality items. Hence, statement 3 is correct.
Therefore, option (d) is the correct answer.
The Indian Space Research Organisation (ISRO) inked a Joint Statement of Intent on Human Space Exploration on the sidelines of the Global Space Exploration Conference (GLEX) – 2025 with:
(a) European Space Agency (ESA)
(b) National Aeronautics and Space Administration (NASA)
(c) Japan Aerospace Exploration Agency (JAXA)
(d) Roscosmos
Explanation
— The European Space Agency (ESA) now has direct and clearer objectives for working with India, and it is willing to collaborate on larger and undiscovered areas of space, according to Dr Josef Aschbacher, the ESA director general.
— The Indian Space Research Organisation (ISRO) and the European Space Agency (ESA) signed a Joint Statement of Intent on Human Space Exploration on the margins of the Global Space Exploration Conference (GLEX) 2025.
— ESA is pleased to collaborate with ISRO and looks forward to investigating large-scale space activities. It is a significant honour for ESA and ISRO to collaborate in the field of space exploration.
— Collaborations are being considered for India's projected Bharatiya Antariksha Station (BAS). India intends to build the space station by 2035. The BAS-1, which has five modules, is expected to launch in 2028.
Therefore, option (a) is the correct answer.
With reference to the tumour marker test, consider the following statements:
1. A tumour marker test measures the number of substances called tumour markers in tissue, blood, urine, or other body fluids.
2. Most tumour markers are proteins made by both normal cells and cancer cells, but they are made in higher amounts by normal cells.
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
— A tumour marker test, according to the National Cancer Institute, counts the number of chemicals known as tumour markers in tissue, blood, urine, or other body fluid. Hence, statement 1 is correct.
— 'The majority of tumour markers are proteins produced by both normal and cancer cells, but cancer cells produce more of them. Genetic changes in cancer tissue, including as gene mutations, gene expression patterns, and other DNA modifications, are also utilised as tumour indicators. Hence, statement 2 is not correct.
— Tumour marker tests include Prostate-specific antigen (PSA), Prostatic acid phosphatase (PAP), CA 125, Carcinoembryonic antigen (CEA), Alpha-fetoprotein (AFP), CA 19-9, CA 15-3, CA 27-29, Lactate dehydrogenase (LDH), and bladder tumour marker investigations.
Therefore, option (a) is the correct answer.
Daily Subject-wise quiz — History, Culture, and Social Issues (Week 109 and 110)
Daily subject-wise quiz — Polity and Governance (Week 110)
Daily subject-wise quiz — Science and Technology (Week 109)
Daily subject-wise quiz — Economy (Week 109)
Daily subject-wise quiz — Environment and Geography (Week 109)
Daily subject-wise quiz – International Relations (Week 109)
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