11. Which of the following clearly define Pyrilla? (UPSC Prelims 1991)
[A] Disease of teeth and gums
[B] An insect pest
[C] A character of ancient Greek mythology
[D] A building heated by solar energy
Show Answer
Correct Answer: B [An insect pest]
Notes:
Adult Pyrilla perpusilla is a pale tawny-yellow, soft-bodied insect with head prominently drawn forward to form a snout. Both adults and nymphs are very active and suck sap from the leaves of sugarcane. On the slightest disturbance, they jump from leaf to leaf.
12. Natural rubber is a plant product which is chemically known by which of the following names? (UPSC Prelims 1992)
[A] Mucilage
[B] Gum
[C] Latex
[D] Resin
Show Answer
Correct Answer: C [Latex]
Notes:
The word latex means only natural rubber. Natural rubber is made from the white sap of some trees such as the Hevea brasiliensis (Euphorbiaceae). Other elastomers, called synthetic rubbers, are made by chemical processes.
13. Which one of the following approaches comes under the category of biotechnology? (UPSC Prelims 1993)
[A] Use of living organisms or substances obtained from them in industrial processes
[B] Modernizing the commercial industries to produce products for use in biological research
[C] Use of modern technology to investigate biological disorders
[D] Use of industrial technology to increase the biosphere
Show Answer
Correct Answer: A [Use of living organisms or substances obtained from them in industrial processes]
Notes:
The biotechnology industry uses bacterial cells for the production of biological substances that are useful to human existence, including fuels, foods, medicines, hormones, enzymes, proteins, and nucleic acids. Another area of biotechnology involves improvement of the qualities of plants through genetic engineering.
14. Which of the following is the quality of the pitch of the voice of women? (UPSC Prelims 1994)
[A] marginally lower than that of men
[B] higher than that of men
[C] much lower than that of men
[D] the same as that of men
Show Answer
Correct Answer: B [higher than that of men]
Notes:
The larger the larynx, the longer and thicker the vocal folds and the lower the pitch of the voice. Typical male voices range in pitch from 85 hertz to 180 hertz. Typical female voices range from 165 hertz to 255 hertz.
15. Which among the following blood groups is referred as the universal donor blood group?
[A] O -ve
[B] O +ve
[C] AB -ve
[D] AB +ve
Show Answer
Correct Answer: A [O -ve]
Notes:
The person with O-ve blood group is considered as the universal donor. Whereas a person with O +ve is not a universal donor as O +ve consists of Rh(Rhesus) factor which makes it incompatible for Rh -ve bloods.
16. Which among the following is responsible for the red colour of blood?
[A] Haemoglobin
[B] Platelets
[C] Plasma
[D] None of the above
Show Answer
Correct Answer: A [Haemoglobin]
Notes:
Haemoglogin pigment is responsible for the red colour of the blood. Haemoglobin is responsible for carrying oxygen from lungs to the tissues of the body.
17. Which branch of medicine deals with the scientific study of the structure of teeth and diseases associated with it?
[A] Virology
[B] Opthalmology
[C] Cosmology
[D] Odontology
Show Answer
Correct Answer: D [Odontology]
Notes:
Odontology is a branch of medicine which deals with the structure and diseases related to the teeth.
18. Which of the following statements are correct with respect to homeostasis?
1. Ecosystems are capable of maintaining their state of equilibrium.
2. They cannot regulate their own species structure and functional processes.
Select the correct option from the codes given below:
[A] Only 1
[B] Only 2
[C] Both 1 & 2
[D] Neither 1 & 2
Show Answer
Correct Answer: A [Only 1]
Notes:
Ecosystems are capable of maintaining their own state of equilibrium. They can regulate their own species structure and functional processes. This capacity of ecosystem of self regulation is referred to as homeostasis.
19. Who discovered nucleus of cell wall?
[A] Theodor Boveri
[B] Robert Brown
[C] Albert von Kolliker
[D] Robert Hooke
Show Answer
Correct Answer: B [Robert Brown]
Notes:
Robert Brown discovered the nucleus in the cell in 1831. The nucleus is a protoplasmic body in eukaryotic cells. It is covered by a double membrane that contains the hereditary details.
20. How many cells are in the human brain?
[A] roughly 171 billion cells
[B] roughly 200 billion cells
[C] roughly 151 billion cells
[D] roughly 250 billion cells
Show Answer
Correct Answer: A [ roughly 171 billion cells]
Notes:
The average male brain contains about 171 billion cells, including about 86 billion neurons.
