BPSC Prelims 2023 Science and Technology Questions with Solutions

Explanation

The human tongue primarily detects five basic tastes: sweet, sour, salty, bitter, and umami. Spicy and pungent sensations, while perceived in the mouth, are not considered true tastes. Instead, they are detected by general pain and temperature receptors (trigeminal nerve endings) rather than taste buds, making them chemical sensations rather than tastes.

Explanation

Dyspnoea is the medical term for shortness of breath, which refers to difficult or labored breathing. Anosmia is correctly defined as the partial or complete loss of the sense of smell. Anorexia, specifically anorexia nervosa, is an eating disorder, not a sleep disorder. Insomnia is a sleep disorder characterized by difficulty falling or staying asleep, and it is not an eating disorder.

Explanation

Pulsars are highly magnetized, rapidly rotating neutron stars that emit beams of electromagnetic radiation. These beams are observed as periodic pulses when they sweep across the Earth, similar to a lighthouse. Neutron stars are extremely dense remnants of massive stars after they have undergone a supernova explosion, and their rapid rotation combined with strong magnetic fields gives rise to the characteristic pulsar phenomenon.

Explanation

In the context of producing lab-grown diamonds (LGDs) through processes like HPHT (High-Pressure/High-Temperature) or CVD (Chemical Vapor Deposition), a small, thin slice of an existing diamond is always used as a "seed" crystal. This diamond seed provides the initial atomic structure upon which new carbon atoms from a carbon source can crystallize and grow, effectively replicating and enlarging the original diamond lattice.

Explanation

All the given liquid options are conductors of electricity to varying degrees. Salted water contains dissolved ions (Na+, Cl-) which act as charge carriers. Orange juice and lemon juice both contain dissolved acids (like citric acid) and other electrolytes, which dissociate into ions in water, allowing them to conduct electricity. A true bad conductor of electricity would be a liquid like pure distilled water or oil, which has very few free ions. Therefore, none of the options A, B, or C are bad conductors.

Explanation

James Watson and Francis Crick are widely recognized for their groundbreaking work in 1953, where they proposed the double helix structure of deoxyribonucleic acid (DNA). Their model, which elucidated how DNA carries genetic information, was significantly informed by the X-ray diffraction images produced by Rosalind Franklin and Maurice Wilkins, along with chemical data from Erwin Chargaff.

Explanation

According to the principles of physics, particularly Galileo's law of falling bodies, all objects falling freely in a vacuum or a negligible atmosphere (like the Moon's surface) experience the same acceleration due to gravity, regardless of their mass. Since both objects start from rest and undergo the same constant acceleration, their velocities will be identical at any given instant during their fall. Inertia is dependent on mass and does not change, and forces would be different for different masses (Force = mass x acceleration).

Explanation

Vector vaccines work by using a modified, harmless version of a different virus, known as a viral vector, to deliver genetic material from the target pathogen (like the spike protein gene of SARS-CoV-2) into the body's cells. Option C describes this fundamental principle by stating that the vaccine works by placing components from the virus within a modified version of a different virus, which then acts as a delivery vehicle. Once inside the cells, this genetic material instructs the cells to produce the pathogen's proteins, triggering an immune response without causing disease.

Explanation

The acronym mRNA stands for Messenger Ribonucleic Acid. It is a type of RNA that carries genetic information copied from DNA during transcription in the nucleus to the ribosomes in the cytoplasm. At the ribosomes, this information is translated to synthesize proteins. mRNA became widely known due to the development and success of mRNA vaccines during the COVID-19 pandemic.

Explanation

A dynamo, commonly known as an electrical generator, is a device that converts mechanical energy into electrical energy. In its most common form, an AC generator (a type of dynamo) produces alternating current by rotating a coil within a magnetic field, inducing an electromotive force. A choke coil is an inductor that opposes changes in current, and a transformer changes the voltage and current of an existing AC supply but does not generate it.

Explanation

Current density (J) is defined as the electric current per unit cross-sectional area. It is a vector quantity because it has both magnitude and direction. The magnitude is the current per unit area, and its direction is conventionally taken to be the direction of the net flow of positive charge carriers, or the direction of the electric field causing the current. Unlike current, which is a scalar, current density explicitly accounts for the direction of charge flow at a point in a conductor.

Explanation

The most useful classification of medications in medical chemistry, particularly from a clinical application standpoint, is often based on their pharmacological effect. This approach categorizes drugs according to their primary therapeutic action or the physiological response they elicit in the body, such as analgesics for pain relief, antihistamines for allergies, or antacids for acidity. This classification helps medical professionals easily identify drugs suitable for treating specific symptoms or conditions, making it highly practical for prescribing and patient care.

Explanation

A substance that slows down a reaction rate is known as an inhibitor or a negative catalyst. Catalytic promoters enhance the activity of a catalyst, thereby increasing the reaction rate. Both homogeneous and heterogeneous catalysts, by definition, increase the rate of a chemical reaction by providing an alternative reaction pathway with lower activation energy. Since none of the options A, B, or C describe a substance that slows down a reaction rate, the correct answer is None of the above.

Explanation

Input nerves, also known as afferent or sensory nerves, transmit signals from sensory receptors to the central nervous system (CNS). Output nerves, also known as efferent or motor nerves, carry commands from the CNS to effector organs like muscles and glands. The central nervous system, comprising the brain and spinal cord, serves as the primary integration center where these input and output pathways converge, process information, and generate appropriate responses.

Explanation

DefExpo-2022, India's flagship exhibition on land, naval, and homeland security systems, was held in Gandhinagar, Gujarat. The overarching theme for this edition of the event was "Path to Pride," reflecting India's aspiration to become a strong and self-reliant defense manufacturing nation. It aimed to showcase indigenous capabilities and promote exports in the defense sector.

Explanation

Net metering is a billing policy that allows consumers who generate their own electricity, typically using solar panels, to send excess electricity back to the utility grid. When a customer's solar panels produce more electricity than their home needs, the surplus energy is exported to the grid, and the customer receives a credit on their electricity bill. This mechanism promotes the adoption of renewable energy by making solar installations more economically viable.

Explanation

In the context of color combinations relevant to printing and light, Magenta is a secondary color formed by mixing Red and Blue (a-2). Cyan is a secondary color created by mixing Green and Blue (d-1). Teal is often described as a mix of Blue, Green, and White (b-3), creating a darker, greenish-blue hue. Mauve is a pale purple, which combines Red, Blue, and White (c-4) to achieve its distinctive shade.

Explanation

The deep-sea submersible that imploded in June 2023 during a voyage to the Titanic wreckage was named Titan. This tragic incident involved the submersible operated by OceanGate Expeditions, leading to the loss of all five passengers aboard. The event garnered significant global attention due to the high-profile nature of the expedition and the subsequent search and rescue efforts.

Explanation

India's Rudrankksh Balasaheb Patil won the gold medal in the Men's 10m Air Rifle event at the 2022 ISSF World Championship in Cairo. This significant achievement not only secured him the top spot but also earned India a quota place for the Paris 2024 Olympics. His victory highlighted his emergence as a prominent talent in shooting sports.

Explanation

The fossils of Tillyardembiids, recognized as the world's first plant pollinators, were discovered recently in the Itat Formation of Siberia, Russia. This significant paleontological finding was announced in 2022, shedding light on the ancient history of plant-insect co-evolution and pollination. The discovery in Russia provided crucial insights into the origin of insect pollination around 160 million years ago.

Explanation

This is a direct substitution coding question where each letter is replaced by a unique symbol. We extract the mappings from the given examples: From 'GAME' is written as ' * %': G ->, A -> /, M -> , E -> % From 'BEAD' is written as '# % ÷ ×': B -> #, E -> %, A -> ÷, D -> × Note that 'A' has two different symbols assigned: '' from 'GAME' and '÷' from 'BEAD'. In such cases, the question typically expects us to use the mapping that leads to one of the given options. To code 'MADE': M -> * (from GAME) A -> ÷ (using the mapping from BEAD, as it leads to a valid option) D -> × (from BEAD) E -> % (consistent from both GAME and BEAD) Combining these, 'MADE' is coded as ' ÷ × %'.

Explanation

Let's deduce the direction of travel for each person: Q travels towards East. M travels towards North. T travels towards the right of Q. Since Q travels East, Q's right is South. Therefore, T travels towards South. S and T travel in opposite directions. Since T travels South, S must travel in the opposite direction, which is North.

So, the derived directions are: Q: East M: North T: South S: North

Now, evaluating the given options: A) M and S travel in the opposite directions. (False, both travel North) B) S travels towards West. (False, S travels North) C) T travels towards North. (False, T travels South) D) M and S travel in the same direction. (True, both M and S travel North) Therefore, option D is definitely true.

Explanation

The given number series is 132, 156, ?, 210, 240, 272. Let's find the differences between consecutive terms. The difference between 156 and 132 is 24. The difference between 240 and 210 is 30. The difference between 272 and 240 is 32. This pattern suggests that the differences are increasing by 2 each time. So, the sequence of differences is 24, 26, 28, 30, 32. Adding 26 to 156 gives 182. To verify, adding 28 to 182 gives 210, which matches the series. Thus, the missing number is 182.

Explanation

The pattern in the given triplets is based on the first and third numbers to derive the middle number. For the first triplet (44, 49, 37): (First number - Third number) multiplied by 7 gives the middle number. (44 - 37) 7 = 7 7 = 49. For the third triplet (58, 35, 53): Applying the same pattern, (58 - 53) 7 = 5 7 = 35. This also holds true. Now, applying this pattern to the second triplet (52, ?, 41): (52 - 41) 7 = 11 7 = 77. Therefore, the missing number is 77.

Explanation

The coding language uses a specific rule for letters based on whether they are vowels or consonants. For consonants, their normal alphabetical position is used (e.g., G=7, R=18, T=20). For vowels, their reverse alphabetical position is used, calculated as (27 - normal position) (e.g., E=5 becomes 27-5=22, A=1 becomes 27-1=26, O=15 becomes 27-15=12).

Applying this rule to VIGOROUS: V (consonant) = 22 I (vowel) = 27-9 = 18 G (consonant) = 7 O (vowel) = 27-15 = 12 R (consonant) = 18 O (vowel) = 27-15 = 12 U (vowel) = 27-21 = 6 S (consonant) = 19 Combining these gives 22187121812619.

Explanation

To find the odd one out, we analyze the alphabetical positions and the differences between consecutive letters in each group. For Q,W,Z,B: Q(17), W(23), Z(26), B(2/28). Differences: W-Q=6, Z-W=3, B-Z=2 (28-26). Pattern: (6, 3, 2). For B,H,K,M: B(2), H(8), K(11), M(13). Differences: H-B=6, K-H=3, M-K=2. Pattern: (6, 3, 2). For M,S,V,X: M(13), S(19), V(22), X(24). Differences: S-M=6, V-S=3, X-V=2. Pattern: (6, 3, 2). For W,C,G,J: W(23), C(3/29), G(7), J(10). Differences: C-W=6 (29-23), G-C=4, J-G=3. Pattern: (6, 4, 3). Groups A, B, and D follow the (6, 3, 2) difference pattern, while group C follows a different pattern (6, 4, 3). Hence, W,C,G,J is the odd one.