Basic Science Flashcards
(509 cards)
1
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2
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3
Q
What is the common name for the botanical family Fabaceae?
A
Legume, bean, or pea family.
4
Q
Name three examples of plants belonging to the Fabaceae family mentioned in the text.
A
Groundnut (Peanut), Soybean, Horse gram.
5
Q
What basic principle does Radar use to detect objects?
A
Transmitting electromagnetic energy towards targets and observing the echoes returned from them.
6
Q
Name two correct applications of Radar mentioned in the text.
A
Meteorology (detecting precipitation) and tracking animal migration (birds, bats).
7
Q
Is Radar technology typically used for identifying narcotics?
A
No, other technologies like X-ray scanners and chemical detectors are used.
8
Q
What is a key recent development in India’s weather radar network?
A
The IMD is expanding its Doppler Weather Radar network, aiming for 73 operational radars by 2025-26 to better track extreme weather events.
9
Q
Which nitrogen compound synthesized in the human body acts as a vasodilator?
A
Nitric oxide (NO).
10
Q
What does vasodilation mean?
A
Dilation (widening) of blood vessels, which increases blood flow.
11
Q
What is a therapeutic use of nitric oxide mentioned in recent research?
A
Managing hypoxic respiratory failure or persistent pulmonary hypertension in newborns.
12
Q
Is Nitrous oxide (N2O) synthesized by the human body?
A
No, it is used for anesthesia but not synthesized by the body.
13
Q
What term describes the overall ability of the body to fight disease-causing organisms?
A
Immunity.
14
Q
Which two special types of lymphocytes are primarily responsible for acquired immunity?
A
B-lymphocytes (B-cells) and T-lymphocytes (T-cells).
15
Q
What type of immunity are B-cells responsible for?
A
Antibody-mediated immunity.
16
Q
What type of immunity are T-cells responsible for?
A
Cell-mediated immunity.
17
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Do T-cells secrete antibodies directly?
A
No, but they help B-cells produce them.
18
Q
What is a recent advancement in immunotherapy involving T-cells?
A
Chimeric antigen receptor (CAR) T-cell immunotherapy shows promise in treating refractory B-cell malignancies.
19
Q
Describe the ant-fungus mutualism involving leafcutter ants.
A
Ants cultivate fungus (like farming), providing leaves as fertilizer and protection, and the fungus serves as food for ant larvae.
20
Q
What was a recent discovery about the fungus cultivated by leafcutter ants?
A
Researchers found new gene groups aiding fungus defense and partnership optimization, plus mobile genetic elements (“jumping genes”).
21
Q
How does increasing the size of the steam vent (hole) affect cooking in a pressure cooker?
A
Leads to more steam escaping, causing a greater reduction in temperature (and potentially longer cooking time).
22
Q
How does adding heavier weight to the pressure cooker lid affect cooking?
A
Creates higher pressure inside, raising the cooking temperature.
23
Q
Why is water called the “universal solvent”?
A
Because it dissolves more substances than any other liquid.
24
Q
What property of water molecules makes water an excellent solvent?
A
Its polarity (positive hydrogen side, negative oxygen side) allows it to be attracted to and interact with other polar molecules and ions.
25
What is a key difference in light emission direction between sodium lamps and LED lamps?
Sodium lamps emit light in all directions, while LEDs are more directional (e.g., 180-degree angle) for targeted lighting.
26
How do the average lifespans of sodium lamps and LED lamps compare for street lighting?
LED lamps generally have a much longer lifespan (25k-200k hours) compared to High-Pressure Sodium lamps (avg. 24k hours).
27
What is a significant advantage of LEDs regarding the color spectrum for street lighting?
LEDs offer more color options and better lighting solutions (higher CRI) compared to the nearly monochromatic yellow glow of sodium lamps.
28
List two key benefits of adopting LED street lighting in India.
Significant energy savings (lower power consumption) leading to reduced costs and carbon emissions; longer lifespan reducing maintenance costs.
29
What is a light-year primarily used to measure?
Astronomical distances.
30
What physical constant is the basis for using light-years as a unit of distance?
The speed of light, which is constant throughout the universe.
31
What structure do plant cells have outside the plasma membrane that animal cells lack?
A cell wall, typically made of cellulose and hemicellulose.
32
Are cell walls living structures?
No, the cell wall is described as a non-living rigid structure.
33
Name two features present in plant cells but absent in animal cells, besides the cell wall.
Plastids and a large central vacuole.
34
Approximately what percentage of a plant cell's volume can the central vacuole occupy?
Up to 90%.
35
Name three pesticides mentioned as banned in Kerala in 2011 to promote organic farming.
Carbofuran, Phorate, Triazophos (also Methyl parathion, monocrotophos, methyl demethon, prophenophos).
36
Who are Denisovans?
An extinct hominin species, closely related to Neanderthals and modern humans.
37
Where were the first Denisovan fossils found in 2010?
Denisova Cave in Siberia's Altai Mountains.
38
What recent fossil discovery expanded the known range of Denisovans?
A jawbone identified off the coast of Taiwan.
39
According to Einstein's General Relativity, how do massive objects affect light?
They distort nearby space-time, causing light to bend from its straight-line path.
40
What cosmic phenomenon did General Relativity predict regarding the universe's structure?
The expansion of the universe over time.
41
What prediction of General Relativity was directly detected by LIGO in 2016?
Gravitational waves [cite: 547, 548, 7.1].
42
How does General Relativity explain gravity?
Gravity emerges from the interaction of space and matter; massive objects warp space-time, causing gravitational attraction.
43
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44
How does the mass of an object relate to its effect on space-time according to General Relativity?
The more massive the object, the more it warps space-time around it.
45
What cosmetic products are mentioned as potentially containing significant amounts of lead?
Lipsticks, mascaras, and eyeliners.
46
What is the regulated limit for lead concentration in cosmetics in India?
20 parts per million (ppm) calculated as lead.
47
What potential health effect of excess lead absorption from cosmetics is mentioned?
Affects the heart, causing hypertension (high blood pressure) and coronary heart disease.
48
What is Brominated Vegetable Oil (BVO) used for in some soft drinks?
To stop ingredients in fruit-flavoured drinks from separating out.
49
What is the recent regulatory status of BVO in the United States?
The FDA revoked the regulation allowing its use in food, effective August 2, 2024, concluding it is no longer considered safe.
50
What is Monosodium Glutamate (MSG)?
A popular flavour enhancer derived from L-glutamic acid, a naturally occurring amino acid.
51
Name two types of food products mentioned that can contain added MSG.
Processed meats (e.g., hot dogs, sausages) and condiments (e.g., ketchup, soy sauce, salad dressing).
52
What does recent research suggest about dietary MSG and brain health?
Dietary glutamate likely has little effect on the brain as almost none passes the blood-brain barrier; no compelling evidence suggests MSG alters brain chemistry in normal amounts.
53
What is the basic structure of a virus?
A segment of nucleic acid (DNA or RNA) surrounded by a protein coat.
54
Can viruses replicate on their own?
No, they must infect host cells and use the host cell's components to make copies.
55
Do viruses carry out metabolic processes or generate ATP?
No, they lack the necessary enzymes and steal energy from host cells.
56
Name three examples of well-known human diseases caused by viruses mentioned in the text.
AIDS, COVID-19, measles, smallpox.
57
What is hibernation?
A state of inactivity and metabolic depression in endotherms (warm-blooded animals).
58
What physiological changes occur during hibernation?
Body temperature is lowered; breathing and heart rates slow down.
59
What is the primary purpose of hibernation for animals?
To protect from cold and reduce the need for food when it is scarce.
60
Name three types of animals mentioned that hibernate.
Bats, Bears, Rodents (also mentioned: bees, snakes).
61
What are potential future applications of inducing hibernation/torpor in humans?
Space exploration (long journeys), medicine (surviving surgeries, treating trauma, heart attack, stroke, organ transplants).
62
What five diseases does the Pentavalent vaccine protect against?
Diphtheria, Pertussis, Tetanus, Hepatitis B, and Haemophilus influenzae type b (Hib) [cite: 570, 6.1].
63
Which disease, once prevalent in India, has now been eradicated?
Smallpox.
64
How is Diphtheria described?
A serious bacterial infection usually affecting mucous membranes of the nose and throat.
65
How is Chickenpox transmitted?
It is an airborne disease spread through coughs and sneezes of an infected person.
66
Describe the simple food chain involving diatoms mentioned in the text.
Diatoms (autotrophs) are eaten by Crustaceans (herbivores), which are then eaten by Herrings (carnivores).
67
What is a potential impact of climate change on diatom blooms?
Rising river temperatures driven by climate change are increasing the risk of spring diatom blooms (and summer cyanobacterial blooms).
68
Mite, Scorpion, and Spider belong to which class of arthropods?
Arachnida.
69
Crabs belong to which group of invertebrate animals?
Crustaceans.
70
What defines a chemical change?
A change in which one or more new substances are formed; also called a chemical reaction.
71
Give two examples of chemical changes mentioned.
Digestion of food, ripening of fruits, fermentation of grapes, souring of milk.
72
Give two examples of physical changes mentioned.
Crystallization of sodium chloride, melting of ice.
73
What is vegetative reproduction in plants?
A form of asexual reproduction where new organisms arise without seeds, often resulting in clones.
74
Does vegetative propagation help eliminate viruses from an infected plant?
No, because a systemically infected plant usually remains infected for its lifetime.
75
Which cell division process is involved in vegetative propagation?
Mitosis.
76
What is the basic definition of photosynthesis?
A biological process converting light energy into chemical energy, stored in organic compounds.
77
What are vitamins?
Organic substances required in adequate quantities for good health, which the body cannot synthesize.
78
Name the four fat-soluble vitamins listed.
Vitamins A, D, E, and K.
79
Name the water-soluble vitamins listed.
Vitamins of B group and Vitamin C.
80
Deficiency of Vitamin C causes which disease?
Scurvy.
81
Deficiency of Vitamin D causes which disease?
Rickets.
82
What symptom is associated with Vitamin E deficiency? What causes night blindness?
Vitamin E deficiency: weakness in muscles. Night blindness: Vitamin A deficiency.
83
What is Mycorrhizae?
A symbiotic association between plant roots and fungi.
84
What is the major role of Mycorrhizae for host plants?
To enhance nutrient and water uptake by exploiting a larger soil volume.
85
List three benefits Mycorrhizae provide to plants.
Resistance to drought, tolerance of pH extremes, resistance to disease infestation (also greater yield, enhanced nutrient uptake).
86
What is the status of Mycorrhizal biofertilizers in the Indian market?
Mycorrhiza-based biofertilizers dominate the market, which is growing due to increased awareness and demand for sustainable agriculture.
87
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88
Besides sexual contact or mother-to-child transmission, how else can Hepatitis B be transmitted?
Contact with blood/body fluids via unsafe injections, needlestick injury, tattooing, piercing, exposure to sharp instruments.
89
Can HIV be transmitted through tattooing?
Yes, transmission is possible through tattooing.
90
How is Chikungunya virus primarily transmitted?
By infected mosquitoes.
91
Name three minerals mentioned as required for muscle contraction.
Calcium, Iron, Sodium.
92
How does calcium trigger muscle contraction?
By reacting with regulatory proteins that normally prevent actin and myosin interaction.
93
How does storing horticultural produce at lower temperatures help preserve it?
It reduces the rate of respiration and delays aging, thus increasing storage life.
94
What technological advancement is helping horticultural storage in India?
Innovative solar-powered cold storage projects are being implemented, reducing costs and spoilage.
95
How do ball bearings reduce friction in machinery like bicycles and cars?
They reduce the effective area of contact between moving parts (like wheel and axle).
96
What causes the apparent change in the sun's size at dusk or color at dawn?
Atmospheric refraction (for size perception) and scattering of sunlight (for color) - these are optical illusions.
97
Why does the sky/sun appear reddish-orange during sunrise and sunset?
Light travels through more atmosphere; shorter wavelengths (blue/green) scatter more, leaving longer wavelengths (orange/red) to reach the observer.
98
Is the moon being visible at dawn an optical illusion?
No.
99
What causes the twinkling of stars?
Atmospheric refraction of starlight as it passes through layers of varying refractive indices.
100
Is the Polestar (Pole Star) appearing stationary an optical illusion?
No, it appears stationary because it is situated close to the direction of the Earth's axis of rotation.
101
What three optical phenomena cause a rainbow?
Dispersion, internal reflection, and refraction of sunlight by water droplets.
102
In which direction is a rainbow always formed relative to the Sun?
In the direction opposite to the Sun.
103
Why do many transplanted seedlings fail to grow?
Most of the delicate root hairs are lost or damaged during uprooting and transplantation.
104
What are biopesticides derived from?
Natural resources such as animals, plants, bacteria, and certain minerals.
105
Name three categories/types of biopesticides mentioned.
Biochemical pesticides, microbial pesticides, and Plant-Incorporated Protectants (PIPs).
106
What is driving the growth of the biopesticide market in India?
Rising demand for organic products, focus on crop protection strategies, increasing farmer awareness.
107
What are some challenges to biopesticide adoption in India?
Lower farmer adaptability/interest, technical challenges in production/application, lack of awareness.
108
Name three examples where the phenomenon of capillarity is utilized.
Kerosene lamps (wick action), blotting paper absorbing ink, water transport in tall trees.
109
Does consuming a soft drink using a straw depend on capillarity?
No, it works because of external pressure differences.
110
What is pollination?
The process of transfer of male pollen to the female part of a flower.
111
What are pollinators? Give three examples of biotic pollinators.
Agents that transfer pollen. Examples: Bats, bees, birds.
112
What is a major factor contributing to pollinator (bee) decline in India?
Habitat change/loss/fragmentation due to rapid urbanization, agricultural expansion, and deforestation.
113
What is the observed impact of pollinator decline on agriculture in India?
Decline in yield growth rate of pollinator-dependent crops, impacting accessibility and cost of nutritious foods.
114
Which three elements are mentioned as primarily responsible for the origin of life on Earth?
Carbon, Hydrogen, and Nitrogen.
115
What is a Virtual Private Network (VPN)?
An encrypted connection over the internet that connects a device to a network, allowing secure data transmission and remote access.
116
Why is the stratosphere preferred for jet aircraft flight?
High visibility (absence of clouds/water vapour) and absence of vertical winds found in the troposphere, reducing disturbances.
117
What are antioxidants?
Molecules that fight harmful free radicals in the body.
118
Why is regular intake of fresh fruits and vegetables recommended regarding antioxidants?
They are good sources of antioxidants, which neutralize free radicals produced during metabolism, potentially reducing risk of diseases like heart disease, diabetes, cancer.
119
What potential health benefits of antioxidants are being researched?
Preventing/slowing Age-related Macular Degeneration (AMD) and cataracts; potential (but debated) roles in cancer prevention and heart health.
120
What force keeps satellites moving in a circular pattern around Earth without falling?
Centripetal force (provided by Earth's gravity).
121
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122
What needs to be balanced for a satellite to remain in orbit around the Earth?
The gravity of the Earth and the momentum of the satellite.
123
What provides the necessary acceleration for a satellite to maintain its orbit?
The acceleration due to Earth's gravity.
124
Compare the typical resolution of standard DVD and High Definition Video (supported by Blu-ray).
DVD: 640x480 pixels (standard definition); Blu-ray supports High Definition Video which is higher in resolution.
125
Compare the storage capacity of a standard DVD and a Blu-ray Disc (BD).
Blu-ray Disc (approx. 50 GB) has a much higher capacity than a standard DVD; one BD can hold the equivalent of more than 10 DVDs.
126
Is the disc thickness different between Blu-ray and DVD?
No, the disc thickness is the same (1.2 mm).
127
Who discovered the basis for blood groups by observing substances on Red Blood Cell surfaces?
Karl Landsteiner.
128
What are the two most important blood group classifications in humans?
ABO and Rh systems.
129
If a couple has blood groups AB positive and O negative, what are the possible blood groups of their biological son?
A or B.
130
What recent advancement in ABO blood group identification research was mentioned?
Development of a novel multiplexed method using QD fluorescence assay (QFA) with magnetic beads for rapid, high-throughput, quantitative detection.
131
How do Compact Fluorescent Lamps (CFLs) and LED lamps produce light differently?
CFLs use mercury and phosphor; LED lamps use semiconductor material.
132
Compare the average lifespans of incandescent, CFL, and LED bulbs.
Incandescent: ~1,000 hours; CFL: ~10,000 hours; LED: ~25,000 hours (or more).
133
Which is generally more energy-efficient: LED, CFL, or incandescent lamps?
LED lamps.
134
What substance are Indian standards trying to limit in CFL bulbs due to disposal concerns?
Mercury (limits amended in IS15111; industry aimed for <3.5 mg using mercury amalgam pills).
135
What is Aspartame?
An artificial, non-saccharide sweetener, approximately 200 times sweeter than sucrose (sugar).
136
Why does Aspartame provide fewer calories than sugar?
It is used in very small quantities due to its sweetness, and it is not readily oxidized in the body.
137
Why can't Aspartame typically be used in baked foods?
It breaks down into amino acids and loses sweetness when heated (unstable at cooking temperatures).
138
What was the outcome of the 2023 WHO/IARC/JECFA re-evaluation of Aspartame?
IARC classified it as "possibly carcinogenic" (Group 2B), but JECFA reaffirmed the acceptable daily intake (ADI) of 40 mg/kg body weight. Many regulatory bodies still consider it safe at permitted levels.
139
Why does the water at the bottom of a lake remain liquid even when the surface freezes in winter?
Due to the anomalous expansion of water; water has maximum density at 4°C. Colder water (including ice at 0°C) is less dense and floats, insulating the water below.
140
Which biological process removes CO2 from the atmosphere, rather than adding it to the carbon cycle?
Photosynthesis.
141
Name three processes that add carbon dioxide (CO2) to the carbon cycle.
Respiration, decay of organic matter, volcanic eruptions.
142
What is an example of a carbon cycle feedback loop potentially accelerating climate change?
Thawing permafrost releases soil carbon into the atmosphere, which amplifies warming and causes more thawing.
143
What process creates artificial trans-fats in the food industry?
Hydrogenation of oils (adding hydrogen to make them more solid).
144
What are the major dietary sources of artificial trans-fats?
Partially hydrogenated vegetable oils (PHVO) / vanaspati / margarine.
145
Are natural trans-fats found in food?
Yes, in small amounts in meats and dairy products.
146
Why are industrially produced trans-fats considered a major health concern?
They are linked to increased risk of heart disease and are a leading cause of death globally.
147
Where is the phloem located in a tree trunk?
Inside the bark.
148
What is the function of the phloem?
To transport soluble organic compounds (sugars produced during photosynthesis) and energy to parts of the tree where needed (like roots).
149
What happens if the bark (and thus phloem) of a tree is removed?
Transport of energy/food is impeded, leading to starvation of roots and eventual death of the tree.
150
How do microwave ovens cook food?
An electron tube (magnetron) produces microwaves, which cause water molecules in the food to vibrate, generating heat.
151
Why do foods with high water content cook quickly in a microwave?
Because microwaves primarily heat by vibrating water molecules.
152
Do microwave ovens cook food from the "inside out"?
No. For thick foods, outer layers are heated by microwaves, and the inside cooks mainly by heat conduction from the outer layers.
153
Is the radiation from microwave ovens considered harmful or carcinogenic under normal use?
No, microwaves use non-ionizing radiation, and leakage is negligible. Scientific research confirms no cancer risk when used correctly.
154
What are the main disinfecting compounds formed when chlorine is added to water?
Hypochlorous acid (HOCl) and hypochlorite ions (OCl-).
155
How does chlorine inactivate microorganisms?
By damaging the cell membrane, allowing chlorine to enter and disrupt cell respiration and DNA activity.
156
Are all microbes effectively inactivated by chlorine?
No, some protozoan cysts are resistant to chlorine.
157
What is the approximate frequency range of radio waves?
From as low as 3 Hz up to 1 gigahertz (10^9 Hz) [corresponding wavelengths thousands of meters to 30 cm].
158
Name four applications of radio waves mentioned in the text.
Standard broadcast radio/TV, shortwave radio, navigation/air-traffic control, cellular telephony, remote-controlled toys, Wi-Fi, Bluetooth, Microwave ovens.
159
Name two reasons why developing an effective malaria vaccine is difficult.
Complex parasite life cycle/immune response; parasite genetic complexity (thousands of antigens); natural infection doesn't confer lifelong immunity.
160
What are the two malaria vaccines recently recommended by WHO?
RTS,S/AS01 (Mosquirix©) and R21/Matrix-M™.
161
Which institution manufactures the R21/Matrix-M™ malaria vaccine?
Serum Institute of India.
162
What are the key properties of neutrinos?
Elementary subatomic particle, no electric charge, very little mass, travel near light speed, 1/2 spin, lepton family, subject to weak force (not strong force).
163
How many types of neutrinos are there, and what are they associated with?
Three types: electron-neutrino, muon-neutrino, tau-neutrino, each associated with the corresponding charged lepton (electron, muon, tau).
164
Are neutrinos rare in the universe?
No, they are the most abundant particles with mass.
165
Name three sources of neutrinos.
Nuclear fusion (like in the sun), nuclear fission (like in reactors), natural radioactivity (like potassium in bananas).
166
Why are neutrinos described as "ghostly" or highly penetrating?
They are not electrically charged and only interact via the very weak force, allowing them to pass through vast amounts of matter without reaction.
167
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168
Name the three types of neutrinos.
Electron-neutrino, Muon-neutrino, Tau-neutrino (each associated with the corresponding charged lepton).
169
Are neutrinos electrically charged? Do they experience the electromagnetic force?
No, they are not electrically charged and do not experience the electromagnetic force.
170
Which fundamental force do neutrinos interact through?
The weak force.
171
How do hydrogen fuel cells produce electricity?
By combining hydrogen and oxygen atoms across an electrochemical cell.
172
What are the main outputs of a hydrogen fuel cell reaction?
Electricity, water, and small amounts of heat.
173
What is the primary environmental advantage of hydrogen fuel cell electric vehicles (FCEVs)?
They produce no tailpipe emissions, only water vapour and warm air.
174
List three disadvantages or challenges associated with hydrogen fuel cell technology.
Difficulty/complexity of extracting hydrogen; high infrastructure investment needed; complexity/expense of hydrogen storage; high flammability of hydrogen.
175
What is the status of hydrogen fuel cell vehicle development in India?
Still in early stages; major companies like Tata, Mahindra, Ashok Leyland have plans; currently no hydrogen cars for sale; Toyota Mirai expected price ~₹60 Lakhs.
176
What does LASIK stand for, and what is its purpose?
Laser-Assisted In Situ Keratomileusis; a procedure using an excimer laser to permanently change the cornea's shape to correct refractive errors (myopia, hyperopia, astigmatism).
177
Can LASIK be performed on a person of any age?
No, there is generally an optimal age range (e.g., 20-40 years mentioned in the text).
178
What do recent studies suggest about the long-term stability of vision after LASIK?
Vision can still change over time (approx. 1% per year); retreatment may be needed for a significant percentage of patients over 10 years.
179
Which enzyme starts protein digestion in the stomach, and under what condition is it most active?
Pepsin; most active in an acidic environment (pH 1.8-3.5).
180
Where does the greater part of protein digestion occur, and which enzymes are primarily responsible?
In the duodenum and upper jejunum, primarily by trypsins (secreted by the pancreas).
181
Can protein digestion still occur effectively after total removal of the stomach?
Yes, usually it is not impaired because trypsins in the small intestine are more powerful.
182
Is Hepatitis B virus (HBV) or HIV typically found in higher concentrations in blood?
HBV can be 100 times more concentrated, making it easier to catch than HIV.
183
What serious liver condition can result from chronic Hepatitis B infection?
Liver cancer (specifically Hepatocellular carcinoma - HCC).
184
What is the general status of Hepatitis B vaccination coverage in India, according to a recent study?
Suboptimal, with limited public knowledge about HBV.
185
Are women or men generally at higher risk of HIV infection from heterosexual vaginal sex?
Women are about twice as likely to acquire HIV.
186
What factors contribute to the increased HIV risk for women during vaginal sex?
Vulnerability of cervical cells; increased risk associated with other genital tract infections (e.g., bacterial vaginosis).
187
What is grafting in horticulture?
Placing a portion of one plant (bud or scion) onto the stem/root/branch of another (stock) so they unite and grow as one.
188
List three purposes for which grafting is used in modern horticulture.
Repair injured trees, produce dwarf plants, increase disease resistance, retain varietal characteristics, adapt to soil/climate, ensure pollination, produce multi-variety plants.
189
Which propagation technique is mentioned for use with jasmine?
Layering.
190
Name three applications of infrared imaging technology.
Earth observation (land/sea temps), night vision (animals), astronomy (detecting cool/distant objects), monitoring fires/lava flows, detecting heat leaks, identifying electrical hotspots [cite: 824, 5.1].
191
How do infrared cameras/goggles generally work?
They use infrared waves to measure the heat released (radiated) by an object.
192
What type of genetic disorder is colour blindness, and which chromosome is involved?
Sex-linked recessive disorder; due to mutation in genes on the X chromosome.
193
Why is colour blindness more common in males than females?
Males have only one X chromosome, while females have two; a female needs the gene on both X chromosomes (or be a carrier with an affected father) to express it.
194
Is there generally a cure or treatment for most types of colour blindness?
No, unless the colour vision problem is related to specific medicines or underlying eye conditions.
195
What is Nitroglycerine?
An explosive liquid, first made by treating glycerol with nitric and sulphuric acid.
196
Is pure liquid nitroglycerine soluble in water?
No, it is insoluble in water (but soluble in alcohols).
197
Why was early use of nitroglycerine dangerous?
It was extremely sensitive to shock, especially when impure.
198
Name three plant products mentioned: Camphor, Chicory, Vanilla.
All three are plant products.
199
Where is camphor traditionally obtained from?
Distillation of the wood of the camphor tree.
200
What part of the chicory plant is commonly used as a coffee substitute/additive?
The roots (baked, roasted, ground).
201
What part of the vanilla plant yields natural vanillin?
The cured pods (fruits).
202
Which colour of light has the highest energy and shortest wavelength within the visible spectrum?
Blue light (also called blue-violet or violet light).
203
What is a potential negative health effect of blue light, especially from digital devices?
Can cause eye strain (due to glare/flickering), potentially leading to headaches, blurred vision, dry eyes, fatigue.
204
Does blue light from digital devices pose a risk of structural damage to eyes below safe limits?
Current standards suggest the risk is below safe viewing limits and shouldn't cause structural changes, though it can affect physiological processes.
205
Place Amphibians, Reptiles, and Mammals in their general evolutionary order of appearance.
Amphibians -> Reptiles -> Mammals.
206
What were the first organisms that invaded land according to the text?
Plants.
207
What characteristic of reptile eggs allowed them to survive better on land compared to amphibian eggs?
They are thick-shelled and do not dry up in the sun.
208
What were the first mammals like, based on fossil evidence?
Shrew-like, small-sized.
209
What reproductive characteristic distinguished early mammals described in the text?
They were viviparous (gave birth to live young) and protected unborn young inside the mother's body.
210
What part of the Crocus sativus L. plant is used to make the spice saffron?
The dried stigmas.
211
What are the main active components responsible for saffron's bioactivity?
Crocetin and its esters (crocins), and safranal.
212
What is the 'Saffron Bowl' project mentioned in the text?
A project under NECTAR that identified locations in Arunachal Pradesh and Meghalaya for saffron cultivation.
213
What is the approximate pH range required for saffron cultivation?
pH 6 to 8.
214
Approximately when did the first cellular forms of life appear on Earth?
About 2000 million years ago (mya).
215
Approximately when did invertebrates become formed and active?
By 500 mya.
216
What is the definition of Infant Mortality Rate (IMR)?
The probability of a child born in a specific year/period dying before reaching age one, subject to age-specific mortality rates.
217
How is IMR typically expressed?
As a rate per 1000 live births.
218
What was the approximate IMR for India in 2023, and what was the recent trend?
Approximately 26.6 deaths per 1000 live births; the rate showed a declining trend from previous years.
219
What is another name for the dry cell battery?
Leclanche cell.
220
What are the main components of a dry cell?
Zinc container (anode), Carbon rod (cathode), powdered Manganese dioxide and carbon surrounding the cathode.
221
What chemicals are used as electrolytes in a typical dry cell?
A moist paste of Ammonium chloride (NH4Cl) and Zinc chloride (ZnCl2).
222
What recent regulation governs battery waste management, including dry cells, in India?
Battery Waste Management Rules, 2022, which mandate Extended Producer Responsibility (EPR) for collection and recycling.
223
What is Bisphenol A (BPA) primarily used for?
Production of polycarbonate plastics and epoxy resins.
224
Name three products mentioned that may contain BPA.
Shatterproof windows, eyewear, water bottles, metal food can linings, bottle tops, water supply pipe linings.
225
Are Langurs considered apes?
No, Langurs are monkeys (subfamily Colobinae).
226
Name three examples of apes mentioned in the text.
Gibbon, Gorilla, Orangutan.
227
Who received the 1962 Nobel Prize for discovering the molecular structure of DNA?
James Watson, Francis Crick, and Maurice Wilkins.
228
Why is the fish Gambusia affinis sometimes released into ponds and wells?
As a biological control agent for mosquitoes, because it eats mosquito larvae.
229
What is a potential negative consequence of introducing Gambusia affinis?
It has become an invasive pest in many waterways globally [cite: 886, 5.1].
230
What is the lightest metal? What is the heaviest natural metal (highest density)?
Lightest: Lithium; Heaviest: Osmium.
231
What type of laser is commonly used as the light source in laser printers?
Semiconductor diode laser.
232
List three other applications of laser diodes mentioned.
Fiber optic communications, barcode readers, laser pointers, CD/DVD/Blu-ray reading/recording, laser scanning, light beam illumination.
233
What is Xenon gas also known as?
Stranger Gas.
234
Does Xenon, a noble gas, form any chemical compounds?
Yes, it is known to form compounds with some elements, unlike typical noble gas behaviour.
235
What are the two main types of coal mine explosions?
Methane explosions and coal dust explosions (also hybrid).
236
What conditions lead to a methane explosion in a coal mine?
A buildup of methane gas contacts a heat source, and there isn't enough air to dilute the gas below its explosion point.
237
What was Agent Orange?
A tactical herbicide (containing dioxin) used by the U.S. military, mainly during the Vietnam War, to clear vegetation.
238
What are some documented long-term health effects of Agent Orange exposure?
Increased rates of various cancers (prostate, lung, non-Hodgkin's lymphoma), Parkinson's disease, peripheral neuropathy, type 2 diabetes, impact on pregnancy/fetal development [cite: 897, 898, 7.1].
239
Who proposed the theory of Continental Drift?
Alfred Wegener.
240
Who provided the first observational evidence for the expanding universe?
Edwin Hubble.
241
What discovery earned Albert Einstein his Nobel Prize in Physics?
His discovery of the photoelectric effect.
242
What are probiotics?
Live microorganisms claimed to provide health benefits when consumed, generally by improving or restoring gut microbiota.
243
What regulatory concerns have been raised in India regarding probiotics?
Dual licensing (as drugs and food), and potentially unsubstantiated health claims associated with products.
244
What does the albedo of an object determine?
Its visual brightness when viewed with reflected light.
245
How does Mercury's albedo compare to Earth's?
Mercury's albedo (0.142) is lower than Earth's (0.367).
246
What is albedo feedback in the context of climate change?
A positive feedback loop where initial warming reduces ice/snow cover (lowering albedo), causing more sunlight absorption, leading to further warming and ice loss.
247
What is the approximate normal pH range for human blood?
Around 7.4.
248
What condition is characterized by blood pH below 7.35? What about pH above 7.45?
Below 7.35: Acidosis; Above 7.45: Alkalosis.
249
What is sexual cannibalism, as identified in spiders?
A female organism killing the male before, during, or after copulation.
250
What does the diet of a King Cobra primarily consist of?
Almost entirely snakes.
251
What is the conservation status of the King Cobra on the IUCN Red List?
Vulnerable.
252
Is Selenium a poor conductor of electricity?
No, it is a non-metal or metalloid with intermediate conductivity properties.
253
What is Robert Webster known for in science?
Research on influenza virus proteins, vaccine/antiviral development.
254
What color results from mixing Red and Blue light (additive)?
Magenta.
255
What color results from mixing Red and Green light (additive)?
Yellow.
256
What color results from mixing Blue and Green light (additive)?
Cyan.
257
What color is highlighted when Magenta (Red+Blue) and Yellow (Red+Green) light are combined?
Red.
258
What color is highlighted when Cyan (Blue+Green) and Magenta (Red+Blue) light are combined?
Blue.
259
Which color model (RGB or CMYK) is additive and used for digital displays? Which is subtractive and used for printing?
RGB is additive (light mixing) for displays; CMYK is subtractive (pigment mixing) for printing.
260
How does the length of a flute relate to the frequency of sound produced?
A flute of smaller length produces waves of higher frequency.
261
In what form do sound waves travel through solids like rocks?
Longitudinal waves.
262
Can low-frequency sound waves from earthquakes be detected?
Yes, infrasound sensors can detect low-frequency waves from earthquakes, especially underwater or in remote areas.
263
In the pitcher plant (Nepenthes), what part of the leaf is modified into the pitcher?
The lamina.
264
What part of the leaf forms the lid of the pitcher in Nepenthes?
The apex of the leaf.
265
What is the appendix (vermiform appendix) anatomically?
A vestigial hollow tube attached to the cecum (beginning of the large intestine).
266
What property allows Crookes glass to be used in sunglasses?
It contains cerium oxide which sharply absorbs harmful UV rays.
267
What is Soda glass primarily composed of and used for?
Silica (~70%), Soda (~15%), Lime (~9%); used for window glass due to light transmission and low melting point.
268
What type of glass is Pyrex, and what is it used for?
Borosilicate glass; used for laboratory glassware and cookware due to heat resistance [cite: 3655, 7.1].
269
What are spiracles in insects?
External openings leading to the internal respiratory system (tracheae).
270
What is the main nitrogenous excretory product in Ureotelic animals?
Urea.
271
What biochemical process leads to the formation of ammonium ions that are converted to urea?
The breakdown of amino acids.
272
Which colors (wavelengths) of light are most effective for photosynthesis?
Red and Blue light (roughly 400-750 nm range).
273
Where does fertilization typically occur in the human female reproductive system?
In the Fallopian tube.
274
What common name is given to Zinc oxide (ZnO), and why?
Philosopher's wool, because the residue formed when alchemists burned zinc had a white woolly texture.
275
What is the basic principle of a CT scan (Computed Tomography)?
It uses X-rays and computer processing to generate a three-dimensional image of the inside of an object.
276
What recent advancements have been made in CT scan technology in India?
Features like cone beam CT, multidetector CT, higher slice systems, spectral imaging, dual-energy capabilities, and AI-based tech improving accuracy.
277
What does CMYK stand for in color printing?
Cyan, Magenta, Yellow, Key (usually black).
278
What is solder, and what is its typical composition mentioned?
A fusible metal alloy used for joining metallic surfaces; typically an alloy of lead and tin.
279
Which food source listed has the highest calcium content per 100g: Rice, Ragi, Skimmed milk, Egg?
Skimmed milk (around 912 mg). Ragi is also high (around 344 mg). Rice and Egg are much lower.
280
What bacterium causes meningococcal disease?
Neisseria meningitidis.
281
How is meningococcal disease primarily transmitted?
Through sharing respiratory and throat secretions (saliva/spit) via close or lengthy contact (e.g., coughing, kissing); NOT mosquito bites.
282
Name three common symptoms of Meningococcal meningitis.
Fever, nausea, vomiting, headache, neck pain.
283
What is the approximate average orbital speed of Earth?
About 30 kilometers per second (or 67,000 mph / 110,000 km/h).
284
Why is cellulose used in making shatterproof glass?
Because cellulose (a polysaccharide) is not soluble in water.
285
How does Mars compare to Earth in terms of orbital period around the Sun?
Mars takes longer (687 Earth days) than Earth (~365.25 days).
286
How does Mars compare to Earth in terms of size (diameter/radius)?
Mars is about half the size (diameter/radius) of Earth.
287
How does Mars compare to Earth in terms of mass and density?
Mars has about 11% of Earth's mass and is less dense.
288
What is the function of the hepatic portal system?
It returns blood from the digestive tract (stomach, intestines, pancreas) and spleen to the liver for processing of nutrients.
289
What is the common bile duct?
A tube carrying bile from the liver and gallbladder to the small intestine (duodenum).
290
What structure joins the pancreas to the common bile duct?
The pancreatic duct (duct of Wirsung).
291
Where do the common bile duct and pancreatic duct release their contents?
Into the duodenum (the first part of the small intestine).
292
In which medium does sound travel fastest: Solid, Liquid, or Gas? Why?
Fastest in solids, because the particles are closest together, allowing vibrations to pass more quickly.
293
Which medium listed would sound travel fastest in: Air, Water, Wood, Vacuum?
Wood (as it's a solid).
294
What treatment options exist for portal hypertension (related to the hepatic portal system)?
Nonsurgical shunt (TIPSS), surgical shunts, or liver transplantation.
295
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296
Name two chemical solvents mentioned as being used in dry cleaning.
Carbon tetrachloride, Benzene.
297
What are diuretics?
Substances that cause the body to make more urine, promoting removal of excess water, salts, poisons, and metabolic products like urea.
298
How might caffeine act as a diuretic?
By increasing blood flow to the kidneys, spurring them to release more water.
299
Can citric acid be used as a substitute for Vitamin C (ascorbic acid) in nutrition?
No, although found together in citrus fruits, they have different chemical structures and citric acid cannot substitute for Vitamin C's nutritional functions.
300
How is Dengue virus primarily transmitted?
By female Aedes aegypti and Aedes albopictus mosquitoes.
301
Are Aedes mosquitoes vectors for other diseases besides Dengue?
Yes, also Chikungunya, Yellow Fever, and Zika viruses.
302
Name three common symptoms of Dengue fever listed.
Retro-orbital (behind eye) pain, nausea, vomiting, rash, muscle/joint/bone pain.
303
What are some recommended prevention strategies for Dengue in India?
Using mosquito repellent, wearing covering clothing, using mosquito nets, eliminating stagnant water breeding grounds, keeping surroundings clean.
304
What causes Foot-and-mouth disease (FMD) in cloven-hoofed animals?
Foot-and-mouth disease virus (FMDV), a picornavirus.
305
What causes Anthrax, and where does it occur naturally?
Bacteria Bacillus anthracis; occurs naturally in soil.
306
What causes Black Quarter disease in livestock?
Bacteria Clostridium chauvoei, whose spores can survive in soil for years.
307
What is Cowpox, and what immunity can it confer in humans?
An eruptive disease primarily of animals (cats, cows) that can transmit to humans and produce immunity to smallpox.
308
What is Liquefied Natural Gas (LNG)?
Natural gas cooled to a liquid state (at about -260°F or -162°C) for shipping and storage.
309
By approximately how much does liquefying natural gas reduce its volume?
About 600 times smaller than its gaseous state.
310
What was India's first LNG import receiving and regasification terminal mentioned?
Dahej LNG terminal in Gujarat (operating since 2004).
311
Name three Natural Gas Liquids (NGLs) that are separated from natural gas/LPG.
Ethane, propane, butane, isobutane, pentane, natural gasoline.
312
List two major uses of NGLs.
Inputs for petrochemical plants, fuel for space heating/cooking, blended into vehicle fuel.
313
What are the main components of Liquefied Petroleum Gas (LPG)?
Propane and Butane.
314
Name two residential or industrial uses of Methane (natural gas).
Heating/cooling homes, direct burning in factories, electricity generation.
315
How does Amoeba reproduce?
Asexually through binary fission (parent cell divides into two identical daughter cells).
316
Is it true that all unicellular organisms reproduce only by asexual methods?
Yes, asexual reproduction (without gametes) is common, and stated as true for all unicellular organisms in the reasoning provided.
317
What is osmosis?
The diffusion of water across a selectively permeable membrane from a region of higher water potential to lower water potential.
318
What is reverse osmosis?
A process using external pressure and a membrane to separate purer water (solvent) from a less pure solution.
319
What is the chemical name for baking soda?
Sodium hydrogen carbonate (NaHCO3).
320
List three uses of baking soda mentioned.
Faster cooking, ingredient in antacids (neutralizes stomach acid), used in soda-acid fire extinguishers. Also mentioned in search: mouthwash, plaque removal, cleaning, deodorizing.
321
How is bleaching powder produced?
By the action of chlorine on dry slaked lime.
322
List three uses of bleaching powder.
Bleaching cotton/linen/wood pulp/laundry, oxidizing agent in chemical industries, disinfecting drinking water.
323
What are some less harsh alternatives to bleach (like bleaching powder) for disinfecting/sanitizing?
Hydrogen peroxide, distilled white vinegar.
324
What is the longest bone in the human body?
Femur.
325
What bacterium causes Cholera?
Vibrio cholerae.
326
What causes Athlete's foot?
A fungal skin infection.
327
Which metal salts produce the following colors in fireworks: Green, Red, Blue, Yellow?
Green: Barium salts; Red: Strontium salts; Blue: Copper salts; Yellow: Sodium salts.
328
What recent regulations regarding fireworks have been implemented in parts of India (like NCR)?
Mandatory use of lower-emission "green" fireworks, bans near silent zones (hospitals, schools), specific time limits for festivals like Christmas/New Year.
329
What is the main constituent of Compressed Natural Gas (CNG)?
Methane (CH4).
330
What is coal gas primarily a mixture of?
Hydrogen, Methane, and Carbon Monoxide.
331
What is water gas primarily a mixture of?
Carbon Monoxide and Hydrogen.
332
How is Alternating Current (AC) typically produced in power plants?
By spinning generators.
333
What is the standard frequency of AC supply in India?
50 Hz (meaning the current direction reverses 50 times per second).
334
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---
335
What negative effect can the glare or flickering from blue light cause after extended exposure?
Eye strain, potentially leading to headaches, blurred vision, dry eyes, and fatigue.
336
Which group of land vertebrates evolved from lobe-finned fish ancestors?
Amphibians.
337
Reptiles evolved from which earlier group?
Amphibians.
338
What type of ancient plants formed coal deposits?
Giant ferns or pteridophytes.
339
What is the commercial part of the saffron plant used as a spice?
The stigma.
340
To which plant family does saffron (Crocus sativus) belong?
Iridaceae.
341
Besides cooking, what other traditional use does saffron have?
Medicinal use due to its therapeutic properties.
342
In India, where is saffron mainly cultivated traditionally?
Jammu & Kashmir and Himachal Pradesh.
343
What did the Infant Mortality Rate (IMR) definition specify about the age of death?
Death occurring before reaching the age of one year.
344
Is the IMR (Infant Mortality Rate) technically a 'rate' or a 'probability'?
Strictly speaking, it is a probability of death derived from a life table (expressed per 1000 live births).
345
What is the main use of Bisphenol A (BPA)?
Production of polycarbonate plastics and epoxy resins.
346
What is the function of Gambusia affinis fish when introduced into ponds?
To control mosquitoes by eating their larvae.
347
What is a significant ecological concern regarding Gambusia affinis?
It has become an invasive pest in many parts of the world, impacting local ecology.
348
What is the common name given to Xenon gas?
Stranger Gas.
349
What tactical herbicide, used mainly in the Vietnam War, contained high levels of dioxin?
Agent Orange.
350
What is a major health risk associated with Agent Orange exposure due to its dioxin content?
It is a carcinogen (can cause cancer). Also linked to other long-term effects like Parkinson's, diabetes, neuropathy, and impacts on pregnancy.
351
What are probiotics?
Live microorganisms claimed to provide health benefits, generally by improving or restoring gut microbiota.
352
Are probiotics generally considered safe to consume?
Yes.
353
What function might probiotics serve in the gut?
Restore gut microbiome composition, introduce beneficial functions, potentially ameliorating/preventing gut inflammation or other diseases.
354
What regulatory aspect concerning probiotics is under review in India?
Issues of dual licensing (as drugs and food) and potentially unsubstantiated health claims, potentially leading to stricter norms.
355
What does the albedo of an object affect?
Its visual brightness when viewed with reflected light.
356
What is the normal pH of human blood?
Around 7.4.
357
What term describes the condition where blood pH is lower than 7.35?
Acidosis.
358
What term describes the condition where blood pH is higher than 7.45?
Alkalosis.
359
In which group of animals mentioned is sexual cannibalism commonly identified?
Spiders.
360
What factor is often related to the occurrence of sexual cannibalism in these species?
The larger size of females due to sexual dimorphism.
361
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362
Does the mass of an object change with altitude?
No, the mass of an object remains constant with altitude.
363
Does the weight of an object change with altitude?
Yes, weight decreases with increasing altitude because acceleration due to gravity decreases.
364
Is the Earth a perfect sphere?
No, due to rotational forces, the Earth is slightly flattened at the poles.
365
What are unsaturated fats chemically characterized by?
They contain more than one carbon-carbon double bond in their fatty acid chains.
366
How do the melting points of polyunsaturated fats compare to saturated fats?
Polyunsaturated fats have lower melting points and are often liquid (oils) at room temperature.
367
Why are unsaturated fats more susceptible to going rancid (oxidation)?
Due to the presence of unstable double bonds which react more readily with oxygen.
368
What determines the moisture-holding capacity of air?
Temperature.
369
Why does water vapour content vary with latitude?
Because temperature varies with latitude (due to differing amounts of sunlight received), affecting air's moisture-holding capacity.
370
How do silicates in synthetic detergents aid cleaning?
They soften water by forming precipitates and provide alkalinity to help suspend soil.
371
What is the role of sodium sulfate in detergent powder?
It acts merely as a filler and does not have an active cleaning role.
372
Name three water-soluble B vitamins found in milk.
Thiamin (B1), Riboflavin (B2), Vitamin B12 (Cobalamin). Milk also contains others like Niacin (B3), B5, B6, Folate, and Vitamin C.
373
Does the velocity of sound in air depend on its amplitude or frequency?
No, the velocity of sound in air is independent of the amplitude, frequency, or wavelength.
374
How does air temperature affect the velocity of sound?
The velocity of sound in air increases as temperature increases.
375
How does air pressure affect the velocity of sound?
The velocity of sound remains unaffected by changes in air pressure.
376
Does humidity affect the speed of sound in air?
Yes, an increase in humidity slightly increases the speed of sound.
377
What is a viroid composed of?
A brief infectious piece of RNA or another nucleic acid.
378
What is a key characteristic distinguishing prions from viruses or viroids?
Prions primarily consist of proteins and lack nucleic acid.
379
How does alcohol consumption affect urine production?
Alcohol acts as a diuretic, promoting urine production.
380
What hormone's release is inhibited by alcohol, leading to increased urine production?
Antidiuretic hormone (ADH) or vasopressin.
381
How does the viscosity of a liquid like glycerine typically change with increasing temperature?
Viscosity tends to decrease as temperature increases.
382
Why do synthetic detergents work better than soaps in hard water?
Detergents form soluble salts with calcium and magnesium ions found in hard water, preventing scum formation and allowing lathering.
383
In which direction are artificial satellites typically launched to achieve Geosynchronous orbit?
Eastward, because the Earth revolves from west to east.
384
What provides the necessary velocity for a satellite to escape Earth's gravity during launch?
The rocket's booster provides the escape velocity.
385
Which ISRO launch vehicle is used for placing satellites like the NVS series into Geosynchronous Transfer Orbit (GTO)?
Geosynchronous Satellite Launch Vehicle (GSLV). ISRO's LVM3 (GSLV Mk III) is also used for heavier launches to GTO.
386
What was the payload for ISRO's GSLV-F15 mission (100th launch from Sriharikota)?
The NVS-02 navigation satellite.
387
What is the difference between essential and non-essential amino acids?
Essential amino acids must be obtained from the diet, while non-essential amino acids can be produced by the body.
388
Name three non-essential amino acids.
Glycine, Serine, Tyrosine.
389
In a cyclone, do surface winds spiral inwards or outwards?
Surface winds spiral inwards toward the center.
390
Does air descend or rise in the center of a cyclone?
Air rises in the center of a cyclone, creating the low-pressure system.
391
What was the name of the severe cyclonic storm forecasted by IMD in October 2024 affecting Odisha and West Bengal?
Cyclone "Dana".
392
Name a recent cyclone (May 2024) that hit Odisha.
Cyclone Remal (classified as Severe).
393
Define Specific Gravity.
The ratio of a substance's density to the density of a reference material.
394
Why does an iron ball float on mercury?
Because the specific gravity of iron (approx. 7.21) is less than that of mercury (approx. 13.56).
395
What is crucial for the origin of new species according to the provided text?
Isolation of gene flow between populations and subsequent significant genetic divergence.
396
What class do ticks and mites belong to?
Arachnida.
397
What are two key characteristics distinguishing arachnids (like spiders, ticks) from insects?
Most arachnids have eight legs and lack antennae or wings.
398
Approximately what percentage of blood volume is made up of Red Blood Cells (RBCs)?
About 45%.
399
What constitutes the largest component of blood by volume after RBCs?
Plasma.
400
What is stem cutting (striking/cloning)?
A method of vegetative propagation where parts of a stem (or sometimes root) are used to grow a new plant.
401
Name two plants commonly propagated using stem cuttings.
Bougainvillea, Grapes (also Carnations, Cocoa mentioned).
402
What optical phenomenon is primarily responsible for the formation of a mirage?
Total Internal Reflection (along with refraction).
403
When does Total Internal Reflection occur?
When light travels within a medium towards a boundary with a medium where speed is higher, and the angle of incidence exceeds the critical angle.
404
According to Lamarckism, what principle explains the loss of limbs in snakes?
The principle of 'use and disuse' of organs.
405
What is Dichogamy in bisexual flowers?
The maturation of male (androecium) and female (gynoecium) parts at different times to prevent self-fertilization.
406
What type of pathogen causes Foot-and-Mouth Disease (FMD)?
A virus (specifically an aphthovirus) [cite: 63, 2.3].
407
Which animals are primarily affected by FMD?
Cloven-hoofed animals like cattle, swine (pigs), sheep, and goats.
408
What is India's goal regarding FMD eradication under the National Animal Disease Control Programme (NADCP)?
Eradication by 2030.
409
Is the FMD vaccination program in India funded by the Centre or States?
It is fully funded by the Central Government.
410
What is Pleiotropy in genetics?
When a single gene influences two or more seemingly unrelated phenotypic traits.
411
What are the bright rings sometimes seen around the sun or moon called?
Halos.
412
How are halos formed around the sun or moon?
By refraction of sunlight or moonlight off ice crystals present in thin cirrus clouds.
413
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414
Which gland secretes Growth hormone (GH) or somatotropin?
The anterior lobe of the pituitary gland.
415
What bodily process stimulates the release of somatotropin (Growth Hormone)?
Exercise.
416
What hormone do the male gonads (testicles) primarily produce?
Testosterone.
417
Name two hormones produced by the female gonads (ovaries).
Estrogens and progesterone.
418
Which hormone is released in short bursts into the bloodstream during stress?
Cortisol.
419
Does light of shorter or longer wavelengths get scattered more easily by atmospheric molecules?
Light of shorter wavelengths (like blue and violet) gets scattered more easily.
420
Does light travel faster in a vacuum or in water?
Light travels faster in a vacuum.
421
How can radio waves be produced?
By oscillations in electrical circuits.
422
How can radio waves induce oscillations in an electrical circuit?
When absorbed, they may create an alternating current with the same frequency as the radio wave itself.
423
What type of radiation do radar speed detectors use?
Microwave radiation.
424
What physical principle allows radar speed detectors to measure vehicle speed?
The Doppler effect, which causes a frequency shift in the reflected waves.
425
Are echinoderms (like starfish) oviparous or viviparous?
Oviparous (they lay eggs).
426
How do roundworms breathe and circulate nutrients?
Through diffusion, as they lack dedicated circulatory or respiratory systems.
427
What structure helps bony fish maintain buoyancy?
Swim bladders.
428
What type of fertilization is characteristic of cartilaginous fish (like sharks and rays)?
Internal fertilization.
429
What is a primary use of Zirconium in nuclear reactors?
For cladding fuel rods and in reactor-core structures due to its unique properties.
430
Is Zirconium itself radioactive?
No, it does not show radioactive properties despite its use in nuclear reactors.
431
Name two physical properties of Zirconium metal.
Malleable, ductile, highly resistant to corrosion.
432
Besides nuclear reactors, name two other uses of Zirconium.
Steel alloys, ceramics, abrasives, lamp filaments, surgical instruments, deodorants.
433
Who first discovered cells?
Robert Hooke in 1665.
434
What is the fundamental structural and functional unit of life?
The Cell.
435
Which cell organelle is known as the "suicidal bag" and functions in waste disposal?
Lysosomes.
436
What is the primary role of Centrosomes in animal cell division?
They play a major role in spindle formation.
437
What are the two types of Endoplasmic Reticulum (ER)?
Rough Endoplasmic Reticulum (RER) and Smooth Endoplasmic Reticulum (SER).
438
What structures are attached to the surface of RER, making it appear 'rough'?
Ribosomes.
439
What is the primary function of Ribosomes?
Protein manufacture/synthesis.
440
Which organelle is involved in the storage, modification, and packaging of cellular products into vesicles?
The Golgi Apparatus (or Golgi complex/body).
441
The Golgi apparatus is also involved in the formation of which other organelle?
Lysosomes.
442
Which organelle is known as the "powerhouse of the cell"?
Mitochondria.
443
In what form do mitochondria release energy for cellular activities?
ATP (Adenosine triphosphate) molecules.
444
What is ATP often called?
The energy currency of the cell.
445
What two components do mitochondria possess that are unusual for organelles, allowing them to make some proteins?
Their own DNA and ribosomes.
446
How does vaccination generally provide immunity?
By introducing antigens (from weakened/inactivated pathogens or their proteins) which stimulate the body to produce antibodies and memory cells.
447
What is generated by vaccines that allows for a rapid response upon subsequent exposure to the pathogen?
Memory cells (B and T lymphocytes).
448
What is passive immunization?
Directly injecting preformed antibodies into a person requiring immediate protection (e.g., for tetanus exposure).
449
Approximately how many frames are typically projected per second in a motion picture?
24 frames per second.
450
For about how long does an image persist on the human retina after the stimulus is removed?
About 1/10th of a second (this phenomenon is called Persistence of Vision).
451
Why do small glass beads fixed on traffic signs glow brightly when light falls on them?
Due to Total Internal Reflection of light within the beads.
452
What are kidney stones (renal calculi) primarily composed of?
Hard deposits made of minerals and salts, often calcium oxalate and uric acid.
453
What conditions in urine lead to the formation of kidney stones?
When urine contains more crystal-forming substances (like calcium oxalate, uric acid) than the fluid can dilute.
454
What gas buildup contacting a heat source can cause explosions in mines?
Methane.
455
Besides methane, what else can be explosive in mines under the right conditions?
Fine particles of coal dust.
456
At which stage of its lifecycle does the silkworm (B. Mori) yield silk fiber?
The pupa stage (when it forms a cocoon).
457
What are the two main protein components of silkworm silk fiber?
A fibroin core and a sericin casing.
458
What is another name for German silver?
Nickel silver.
459
What are the primary metals composing German silver?
Copper (Cu), Zinc (Zn), and Nickel (Ni).
460
Does German silver contain any actual silver (Ag)?
No.
461
What is solder?
A metal alloy used to join two other metals together by melting.
462
What are the typical components of soft solders (Lead Alloy Solders)?
Lead (Pb) mixed with Tin (Sn).
463
What approximate chlorine content should fresh bleaching powder have?
33% or more.
464
Why should bleaching powder be stored in dry conditions away from direct sunlight?
Because it is unstable, and chlorine content reduces over time, especially under moist conditions or sunlight.
465
What is Hyponatremia?
Abnormally low concentration of sodium in the blood.
466
What is Hemophilia?
An inherited genetic bleeding disorder where blood does not clot properly due to a lack of specific clotting factors.
467
What is Diabetes primarily related to?
Either insufficient insulin production by the pancreas or the body's inability to use insulin effectively, leading to issues regulating blood glucose.
468
What causes Rickets in children?
Usually an extreme and prolonged deficiency of Vitamin D, leading to softening and weakening of bones.
469
What type of infection is Ringworm?
A contagious fungal infection caused by mold-like parasites living on skin cells.
470
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471
What is the normal blood sugar level range (in mg/dL) approximately 2 hours after eating?
Less than 140 mg/dL.
472
What blood sugar reading (mg/dL) 2 hours after eating typically indicates diabetes?
More than 200 mg/dL.
473
What blood sugar range (mg/dL) 2 hours after eating indicates prediabetes?
Between 140 and 199 mg/dL.
474
What is a Phytotron?
A controlled environment research facility used to study the effects of the environment on plants.
475
What are the two major functions of gonads in adults?
Steroid hormone production and gametogenesis (production of gametes).
476
Name a primary hormone associated with female gonads (ovaries).
Progesterone (Estrogens also mentioned).
477
Where is the Pituitary Gland located?
In a bony cavity called sella turcica, attached to the hypothalamus.
478
Name the two main hormones secreted by the endocrine part of the pancreas that regulate blood glucose.
Insulin and glucagon.
479
Name a hormone secreted by the pancreas that inhibits the release of insulin and glucagon.
Somatostatin.
480
Name two steroid hormones secreted by the adrenal gland.
Cortisol and aldosterone.
481
What is Nichrome?
An air-stable resistance-heating alloy, primarily composed of nickel, chromium, and iron.
482
What are key properties of Nichrome that make it suitable for heating elements?
Remains ductile after long use, has high hot and creep strength compared to other alloys.
483
How does increasing temperature generally affect the rate of chemical reactions?
Increasing temperature increases the rate of reaction.
484
Approximately how much does a 10°C decrease in temperature reduce a chemical reaction rate?
It reduces the rate by about half.
485
How does pressure arise in a gas?
From the collisions of gas molecules with the walls of their container.
486
What does the temperature of a gas measure regarding its particles?
Temperature is a measure of the average kinetic energy of the gas particles.
487
How many binary digits (bits) typically make up one byte in computer systems?
Eight binary digits.
488
What does a byte usually represent in computer systems?
A character, such as a letter, number, or typographic symbol.
489
What is the function of a 'choke' or 'reactor' in a fluorescent lamp circuit?
It limits the electrical current to prevent damage to the lamp.
490
What technology does a Compact Disc (CD) audio player use to read the stored music data?
A laser beam.
491
How is music stored on a CD?
In digital format (a series of 0s and 1s).
492
What process converts the digital data on a CD into the sound we hear?
A Digital-to-Analog (D/A) converter within the CD player.
493
What phenomena cause the rainbow colors seen when white light reflects off a CD surface?
Interference patterns, caused by the reflection, diffraction, and transmission of light from the disc's small ridges.
494
Can a person propel themselves on a completely frictionless surface by whistling? Why?
Yes, because expelling air (whistling) creates an equal and opposite reaction force, propelling the person (Newton's 3rd Law).
495
What principle states that the momentum of a system cannot change if no external force acts on it?
The principle of conservation of momentum.
496
What are the sex chromosomes for biological males and females in humans?
Males typically have XY chromosomes; females typically have XX chromosomes.
497
What happens to one of the X chromosomes in female embryonic development?
It is randomly and permanently inactivated in cells other than egg cells.
498
Which parent's contribution determines the biological sex of a child?
The male parent, by contributing either an X or a Y chromosome via sperm.
499
What refrigerant is commonly used in large cold storage plants?
Ammonia (NH3).
500
What type of refrigerant was commonly used in older domestic refrigerators?
Chlorofluorocarbons (CFCs), specifically CFC-12 as the refrigerant.
501
What was CFC-11 typically used for in domestic refrigerators?
As the blowing agent for the insulating polyurethane foam.
502
Give one reason why Ammonia (NH3) is considered a good refrigerant for large systems.
It can be liquefied at low pressures; it breaks down quickly in the environment; it is efficient.
503
What is muscle fatigue?
A decrease in maximal force or power production in response to contractile activity.
504
What substance accumulates in muscles during prolonged strenuous physical work, causing fatigue?
Lactic acid.
505
Name one condition (other than exercise) that can cause muscle fatigue.
Addison's disease, age, anaerobic infections, anemia, anxiety.
506
What is Anodising?
An electrochemical process used to form a thick, protective oxide layer on the surface of a metal, particularly aluminum.
507
How does anodising improve aluminum's properties?
It makes the naturally occurring thin oxide layer thicker, significantly improving resistance to further corrosion.
508
What is the simple definition of water hardness?
The amount of dissolved calcium (Ca) and magnesium (Mg) minerals in the water.
509
Why does soap not lather well in hard water?
Calcium and magnesium ions in hard water react with soap to form insoluble precipitates (scum), preventing lathering.
