1. In genetics, the Reverse transcriptase helps in which among the following transcriptions?
[A] Single stranded DNA into double stranded DNA
[B] Single stranded RNA into double stranded DNA
[C] Single Stranded RNA into double stranded RNA
[D] Double Stranded DNA into single stranded RNA
Show Answer
Correct Answer: B [Single stranded RNA into double stranded DNA]
Notes:
Reverse transcriptase helps in Single Stranded RNA into double stranded RNA transcriptions. Reverse transcriptase (RT), also known as RNA-dependent DNA polymerase. It is used to generate complementary DNA (cDNA) from an RNA template.
2. Which type of acid is predominantly found in fruits like Grapes, Bananas, and Tamarind?
[A] Lactic Acid
[B] Oxalic Acid
[C] Salicylic Acid
[D] Tartaric Acid
Show Answer
Correct Answer: D [Tartaric Acid]
Notes:
Tartaric acid is a white, crystalline organic acid that occurs naturally in many fruits, most notably in grapes, bananas, and tamarind. Tartaric acid is used in several food products for its sour taste and antioxidant properties. It has a very sour taste and is a key raw material for making wine, where it plays a vital role in maintaining the color, taste, and texture of the product.
3. Which among the following cells is capable to develop in any of the type of cell?
[A] Endothelial
[B] Endodermal
[C] Stem
[D] None of the above
Show Answer
Correct Answer: C [Stem]
Notes:
A stem cell is a cell with the unique ability to develop in any of the type of cell. In the future they may be used to replace cells and tissues that have been damaged or lost due to disease.
4. Which component in light causes suppression of melatonin produced by the pineal gland?
[A] Red
[B] Blue
[C] Green
[D] Indigo
Show Answer
Correct Answer: B [Blue]
Notes:
Blue component in light causes suppression of melatonin produced by the pineal gland. Melatonin regulates the sleep–wake cycle. Natural levels of melatonin in the blood are highest at night.
5. Which among the following is homologous to a human arm?
[A] Wing of an insect
[B] Leg of a lobster
[C] Lateral Fin of a whale
[D] Front leg of a reptile
Show Answer
Correct Answer: C [ Lateral Fin of a whale]
Notes:
The lateral fin of the whale consists of the same bones as a human’s arm, the radius, ulna, and humerus. These structures are considered to be homologous because the underlying structure is similar and, therefore, humans and whales share a common ancestor. The lobster’s leg, the reptile’s front leg, and the insect’s wing are analogous to the human’s arm. They have a common function but no common structure, and they do not share a common ancestor.
6. Which movements of “Touch me not plant” lead to closing of its leaves when touched?
[A] Nyctinastic movements
[B] Seismonastic movements
[C] Chemonastric movements
[D] Photonastic movements
Show Answer
Correct Answer: B [Seismonastic movements]
Notes:
Seismonastic Movement is caused by the mechanical stimuli like shock, touch, fast moving wind, etc. Mimosa pudica is a perennial herb which is also known as the touch me not plant or the sensitive plant, is well-known for closing its leaves (or folding its leaves inwards) when touched.
7. Which among the following is not a connective tissue?
[A] Blood
[B] Skin
[C] Cartilage
[D] Bone
Show Answer
Correct Answer: B [Skin]
Notes:
The connective tissues include several types of fibrous tissue that vary only in their density and cellularity, as well as the more specialized and recognizable variants—bone, ligaments, tendons, cartilage, and adipose tissue. Skin is not a connective tissue. It is the body’s largest organ and consists of multiple layers, including the epidermis (outermost layer) and the dermis (deeper layer). Skin primarily serves as a protective barrier and regulates temperature, but it is mainly classified as an epithelial tissue due to its structure and function.
8. The vocal cords in men are about how many mm long?
[A] 40mm
[B] 20mm
[C] 10mm
[D] 30mm
Show Answer
Correct Answer: B [20mm]
Notes:
The vocal cord in women is about 15 mm long; in men vocal cords are about 20 mm long and children have very short vocal cords.
9. Which of the following is the main constituent of the Gobar gas?
[A] Carbon dioxide
[B] Methane
[C] Ethylene
[D] Carbon monoxide
Show Answer
Correct Answer: B [Methane]
Notes:
Biogas or Gobar gas is produced by the breakdown of organic matter in the absence of oxygen. It can be produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste or food waste. It is a renewable energy source. It comprises primarily methane (CH4) and carbon dioxide (CO2) and may have small amounts of hydrogen sulphide (H2S), moisture and siloxanes. It is produced by anaerobic digestion.
10. Which of the following contain a protein named Alpha-keratin? (UPSC Prelims 1997)
[A] Blood
[B] skin
[C] wool
[D] eggs
Show Answer
Correct Answer: B [skin]
Notes:
Alpha-keratin, or α-keratin, is a type of keratin found in vertebrates. This protein is the primary component in hair, horns, mammalian claws, nails and the epidermis layer of the skin. α-keratin is a fibrous structural protein, meaning it is made up of amino acids that form a repeating secondary structure.