11. Which among the following is most distantly related to other three animals?
[A] Walrus
[B] Sea Lion
[C] Seals
[D] Sperm whale
Show Answer
Correct Answer: D [ Sperm whale]
Notes:
Seals, Walruses and Sea lions are Mammals belonging to a single taxonomic group ( a clade) called Pinnipedia, which means fin footed. All of them are semi-aquatic marine mammals. They belong to the order Carnivora and their closest living relatives are bears. They are characterized by modification of limbs to flippers. Pinnipeds are mammals with four flippers — one pair in front and one at the back. They are warm-blooded, nurse their young, breathe air and have hair. The sea lion has small, tiny external ear flaps. Seals have no flaps. The front flippers of sea lions are long, have no hair and nails. Seals’ front flippers are short, blunt, covered with hair with nails on the ends. Sea lions can turn their hind flippers forward to move on land but seals cannot do so.
12. What is common to the techniques (i) in vitro fertilisation, (ii) Cryo preservation and (iii) tissue culture?
[A] All are in situ conservation methods
[B] All are ex situ conservation methods
[C] All require ultra modern equipment and large space
[D] All are methods of conservation of extinct organisms
Show Answer
Correct Answer: B [All are ex situ conservation methods]
Notes:
In vitro fertilisation, cryo preservation and tissue culture all are ex situ conservation methods. Ex situ conservation is a technique of conservation outside natural habitats.
13. Which among the following is the name given to the ductless and secretory glands in the human body? (UPSC Prelims 1983)
[A] Endocrine glands
[B] Exocrine glands
[C] Salivary glands
[D] None of the above
Show Answer
Correct Answer: A [Endocrine glands]
Notes:
Ductless glands which are also known as internally secreting glands or endocrine glands secrete their products or hormones directly into the blood stream in response to instructions from the brain.
14. Who among the following carries the Haemophilia, a hereditary disease? (UPSC Prelims 1993)
[A] females and expressed by females
[B] females and expressed by males
[C] males and expressed by females
[D] males and expressed by males
Show Answer
Correct Answer: B [females and expressed by males]
Notes:
If he inherits his mother’s other X chromosome, he will have normal blood clotting. So a carrier’s son has a 50% chance of having hemophilia. A baby girl will inherit an X chromosome with a dominant gene for normal blood clotting from her father. So the daughter will not have hemophilia.
15. 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.
16. Which one among the following is not a good source of nutritional calcium? (UPSC Prelims 2006)
[A] Rice
[B] Ragi
[C] Skimmed milk
[D] Egg
Show Answer
Correct Answer: B [Ragi]
Notes:
Ragi contains only 344 mg of calcium and in 100 gm of ragi protein is 7.3 gm., fat 1.3 gm, fibre 3.6 gms, carbohydrates 72 gms, moisture 13.1 gm.
17. Which pigment is responsible for the colour of healthy skin in human beings?
[A] Bilirubin
[B] Haemoglobin
[C] Melanin
[D] Progesterone
Show Answer
Correct Answer: C [Melanin]
Notes:
The single most factor responsible for the cpolour of the skin is the pigment melanin. It is secreted by the melanocytes within the skin.
18. Which of the following branch of biology deals with the study and rearing of grasses?
[A] Agrostology
[B] Agronomy
[C] Dendrology
[D] Phenology
Show Answer
Correct Answer: A [Agrostology]
Notes:
Agrostology, the branch of botany concerned with the study of grasses, especially their taxonomy.
19. Which of the following was invented by Jonas Salk?
[A] Polio Drop
[B] Polio Vaccine
[C] BCG Vaccine
[D] aspirin
Show Answer
Correct Answer: B [Polio Vaccine]
Notes:
The first effective polio vaccine was developed in 1952 by Jonas Salk. Polio, or poliomyelitis, is a disabling and life-threatening disease caused by the poliovirus.
20. Who among the following discovered the cytoplasm?
[A] Rudolf von Kölliker
[B] Camillo Golgi
[C] Christian de Duve
[D] Walther Flemming
Show Answer
Correct Answer: A [Rudolf von Kölliker]
Notes:
The term was introduced by Rudolf von Kölliker in 1863. It was originally synonymous with protoplasm, but later changed to mean cell matter and organelles outside the nucleus.