UPSC 2010 Science and Technology Questions with Answers

Explanation

CyberKnife is an advanced radiosurgery technology that allows real-time tracking and adjustment of radiation beams, ensuring precise targeting of tumors while minimizing damage to surrounding healthy tissues. These features make CyberKnife highly effective for treating tumors in sensitive areas such as the brain, spine, and lungs. Options (a), (b) and (c) are correct: CyberKnife is a non-invasive robotic radiosurgery system used to treat cancerous and non-cancerous tumors. It is a robotic image-guided system, capable of delivering extremely precise doses of radiation with sub-millimeter accuracy.

Option (d) is incorrect: CyberKnife is not designed to map the spread of tumors in the body. Its role is strictly limited to treating targeted tumor regions. Imaging techniques such as PET scans, CT scans, and MRIs are used to identify and map tumor spread, whereas CyberKnife focuses solely on delivering radiation therapy with exceptional precision.

Explanation

Golden rice is a genetically modified variety of rice specifically engineered to address vitamin A deficiency. The grains of Golden rice are biofortified with beta-carotene, a precursor of vitamin A (pro-vitamin A). When consumed, beta-carotene is converted into vitamin A in the human body, making golden rice an important dietary intervention to combat vitamin A deficiency, particularly in developing countries where this deficiency is prevalent and can lead to serious health issues like blindness.

Explanation

The 2.4 GHz and 2.5 GHz ISM band (Industrial, Scientific, and Medical) is a part of the radio frequency spectrum commonly used for short-range communication technologies. This range is globally available for unlicensed use, making it ideal for a variety of wireless communication applications. Bluetooth devices, cordless phones, microwave ovens, Wi-Fi baby monitors, wireless cameras, and RFID systems operate in the 2.4 to 2.5 GHz range of the radio frequency band. While it allows a variety of devices to operate within it, managing interference is a key challenge in environments with multiple devices using the same frequency. This range is commonly used due to its balance between range and data capacity, making it suitable for short-range communication and other applications.

Explanation

LASIK is primarily used to treat refractive errors such as nearsightedness (myopia), farsightedness (hyperopia), and astigmatism. LASIK uses a laser to reshape the cornea, allowing light entering the eye to be properly focused onto the retina, improving vision. The goal of LASIK is to correct refractive errors and thereby reduce or eliminate the need for corrective eyewear like glasses or contact lenses. LASIK is typically not recommended for individuals under the age of 18 because their eyes may still be changing. Additionally, people over the age of 40 may not be ideal candidates due to presbyopia, a condition that affects near vision.

Explanation

Option (c) is correct: DSL (Digital Subscriber Line) is a wired broadband technology that uses telephone lines to transmit digital data. It is used for high-speed internet connections, but it is not a wireless technology. It does NOT belong to the GSM (Global System for Mobile Communication). DSL is a wired broadband technology that provides internet access over telephone lines and is unrelated to mobile networks. Options (a), (b) and (d) are incorrect:

EDGE (Enhanced Data Rates for GSM Evolution) belongs to the GSM family. It is an enhancement of GPRS (General Packet Radio Service) and is considered part of 2.5G and 2.75G networks within the GSM framework. LTE (Long-Term Evolution) belongs to the GSM family. LTE is a 4G technology that evolved from GSM and UMTS (Universal Mobile Telecommunications System). It provides high-speed wireless communication but is not strictly GSM-based; however, it is considered part of the evolutionary path of GSM networks.

Explanation

Oceansat-2, launched by ISRO in 2009, is an Earth observation satellite designed to study oceanic and atmospheric conditions. It supports applications like ocean forecasting, fishing zone mapping, and monitoring coastal and atmospheric parameters.

Statement 1 is correct: Oceansat-2 is equipped with sensors such as the Scatterometer and Ocean Color Monitor (OCM), which help assess atmospheric parameters like water vapour content.

Statement 2 is correct: By measuring sea surface winds and temperatures, the satellite is capable of understanding and predicting monsoon dynamics, which are closely tied to oceanic and atmospheric interactions.

Statement 3 is correct: The Ocean Color Monitor onboard can detect chlorophyll concentrations, sediment levels, and other indicators of water quality, helping monitor and assess pollution in coastal regions effectively.

Explanation

Bhuvan (means Earth in Sanskrit) is a Geoportal of ISRO, to evince the Indian Earth Observation capabilities from the Indian Remote Sensing (IRS) series of satellites. It is an interactive versatile Earth-Browser which showcases multi-sensor, mutli-platform and multitemporal images with capabilities to overlay thematic information along with near real-time information from Automatic Weather Stations (AWS), Potential Fishing Zone (PFZ) information, disaster support related information like forest fire alerts, periodic agricultural drought assessment etc. Bhuvan provides 2D/3D imaging and visualization of India’s geographic data. It allows users to access and analyze spatial information, similar to Google Earth, but with a focus on Indian data and applications such as urban planning, agriculture, and disaster management. But due to security concerns, the images available do not include any military installations in India.

Explanation

Acid rain occurs when certain pollutants in the atmosphere react with water vapor to form acids, which then fall to the ground as rain, snow, or fog. The pollutants responsible for acid rain are primarily oxides of nitrogen and oxides of sulfur.

Option 1 is incorrect: Hydrogen itself does not form acidic oxides under typical environmental conditions. The concept of oxides of hydrogen is not commonly associated with acid rain.

Option 2 is correct: Nitrogen oxides, such as nitrogen dioxide, combine with water vapor in the atmosphere to form nitric acid, which contributes to acid rain.

Option 3 is correct: Sulfur oxides, such as sulfur dioxide, react with water vapor to form sulfuric acid, which is another major contributor to acid rain.

Explanation

When carbon monoxide (CO) is inhaled, it binds to hemoglobin in red blood cells with a much stronger affinity than oxygen. Hemoglobin normally binds to oxygen to transport it throughout the body, but CO binds more tightly, forming carboxyhemoglobin. This reduces the ability of hemoglobin to carry oxygen effectively, leading to a decrease in oxygen supply to vital organs and tissues. Carbon monoxide (CO) has approximately 200-250 times more affinity for hemoglobin than oxygen, which means it competes with oxygen for binding sites on hemoglobin.

Explanation

Maize is widely cultivated for the production of ethanol, which is used as a biofuel. Ethanol is derived from the fermentation of sugars and starches found in maize kernels. The United States and Brazil are among the largest producers of maize-based ethanol, which serves as a renewable energy source and an alternative to fossil fuels. Options (a), (c), and (d) are incorrect:

Jatropha is primarily cultivated for its seeds, which contain oil that can be converted into biodiesel. It is not used for ethanol production because it does not contain significant amounts of starch or sugars that can be fermented into ethanol. Pongamia (also known as Millettia pinnata) is an oilseed crop. Its seeds contain oil that are used popularly for biodiesel for biodiesel production, not ethanol. Sunflower is primarily grown for edible oil production, sunflower does not have the starch or sugar content necessary for ethanol production.