1. The web of the spider is made up of which among the following?
[A] Carbohydrate Polymers
[B] Proteins
[C] Lipids
[D] Polysaccharides
Answer: B [Proteins]
Notes:
Spiders use their silk to make web. Spider silk is made out of protein.
2. When a tube light breaks, a cracking sound is produced because ____?
[A] Pressure inside the lamp is less than atmospheric pressure
[B] Pressure inside the lamp is more than atmospheric pressure
[C] The lamp is filled with reactive gases
[D] The lamp is filled with mercury vapour
Answer: A [Pressure inside the lamp is less than atmospheric pressure]
Notes:
A fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon, xenon, neon, or krypton. The pressure inside the lamp is around 0.3% of atmospheric pressure.
3. In which parts of the body glycogen is stored mainly?
[A] cartilages & bones
[B] Liver and muscles
[C] Spleen
[D] Lungs
Answer: B [liver and muscles]
Notes:
Glycogen is stored mainly in liver and muscles. It is a multibranched polysaccharide of glucose. It serves as a form of energy storage in animals, fungi, and bacteria.
4. Which among the following is correct regarding Hemophilia?
[A] The disease is carried by females and expressed by males
[B] The disease is carried by males and expressed by females
[C] The disease is carried by males & females and expressed by males
[D] None of the above
Answer: A [the disease is carried by females and expressed by males]
Notes:
Hemophilia is an inherited bleeding disorder in which a person lacks or has low levels of certain proteins called “clotting factors” and as a result, the blood doesn’t clot properly. Clotting factor is a protein in blood that controls bleeding. If you have hemophilia, you may bleed for a longer time after an injury than you would if your blood clotted normally. Hemophilia is quite rare. About 1 in 10,000 people are born with it.
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5. From which part of the plant Glycyrrhiza glabra, Liquor ice or Mulethi is obtained?
[A] Leaves
[B] Roots
[C] Fruits
[D] Stem
Answer: B [Roots]
Notes:
Mulethi is powdered liquor ice root and is an effective expectorant used since ancient times in Ayurvedic medicines. It is also used in Jastimadhu which is a tooth powder. Many cough syrups today contain Liquor ice as an ingredient. It is also used in mouth ulcers and peptic ulcers.
6. How does calcium carbide ripen mangoes?
[A] It reacts with moisture and releases Ethylene
[B] It reacts with moisture and releases Acetaldehyde, which in turn releases ethylene
[C] It reacts with starch and releases Acetylene
[D] It reacts with moisture and releases Ethane
Answer: A [It reacts with moisture and releases Ethylene]
Notes:
For reasons of safe transportation of fruits, mangoes, bananas etc are picked before they ripen fully. Slightly green harvested mangoes are subjected to small containers of calcium carbide (CaC2) with a plastic covering. CaC2 reacts with the moisture in the air to release acetylene (or ethane) gas as follows:
CaC2 + 2 H2O – C2H2 + Ca(OH)2
This option may give you slightest confusion if you don’t know the difference between Ethylene and Ethane (Acetylene). Both are chemical substances produced by fruits to accelerate the normal process of fruit maturation — are a ripening hormone. Ethylene is C2H4 and has a carbon-carbon double bond. Acetylene is C2H2 and has a carbon-carbon triple bind. Acetylene contains more energy and burns hotter than ethylene. Ethylene is a gaseous compound, Acetylene is the chemical compound, which is the simplest alkyne and is also a hydrocarbon while Ethylene is the simplest alkene and classified as an unsaturated hydrocarbon. I hope you will never forget it now.
7. Silica gel is used in a transformer:
1. as a coolant
2. To remove the moisture from air
3. To decrease the dielectric strength of transformer oil
Which of the above statements is/are correct?
[A] Only 1 & 2
[B] Only 2 & 3
[C] Only 2
[D] 1, 2 & 3
Answer: C [Only 2]
Notes:
Silica gel is used in a transformer for the absorption of moisture from air during breathing out of the transformer. If the relative water moisture content is increased, then this leads to the decrease of the dielectric strength of mineral oil. The result is that the breakdown voltage drastically reduced in the range of 20-50% of relative water content.
8. Identify the element with the help of given information:
1. It was the first element to be discovered with a spectroscope
2. It remains liquid at room temperature
3. It reacts violently with water so it is kept under a layer of kerosene or mineral oil
4. It is the softest known metal on earth
Select the Answer from options given below:
[A] Cesium
[B] Mercury
[C] Gold
[D] Tin
Answer: A [Cesium]
Notes:
All given properties are of Cesium.
Cesium was the first element to be discovered with a spectroscope. Cesium is the softest known metal on earth. It remains liquid at room temperature. Since it reacts violently with water, it is kept under a layer of kerosene or mineral oil.
9. Why a small liquid drop is in spherical shape?
[A] due to surface tension
[B] Due to low viscosity
[C] due to hydrogen bonding
[D] due to low density
Answer: A [due to surface tension]
Notes:
For a given volume, the sphere has minimum surface area. A small liquid drop has spherical shape as due to surface tension the liquid surface tries to have minimum surface area.
10. Which of the following represents the speed of a sound wave?
[A] Wavelength x frequency
[B] 2 x wavelength x frequency
[C] wavelength/frequency
[D] (wavelength x frequency)/2
Answer: A [wavelength x frequency]
Notes:
The speed of sound is defined as the distance which a point on a wave, such as a compression or a rarefaction, travels per unit time. It is represented by s = wavelength x frequency.
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