Taxonomy (Biology) Part-II

Total Questions: 50

41. The venom of cobra is— [Uttarakhand P.C.S. (Pre) 2010]

Correct Answer: (a) Neurotoxic 
Solution:

The venom of the cobra is mainly neurotoxic, which affects nervous tissues. It has some other major compound as cardiotoxic. Toxins present are mainly protein and polypeptide.

It disrupts the electrical impulses that nerves and muscles use to function, leading to neurological effects like paralysis. The National Institutes of Health (NIH) (.gov) notes that cobra venom contains toxins like α-neurotoxins that target the neuromuscular junction, disrupting the transmission of nerve signals.

Neurotoxins are a class of toxins that affect the nervous system. They interfere with the transmission of nerve impulses, which are crucial for muscle control, sensory perception, and other vital bodily functions.

42. For which one of the following snakes is the diet mainly composed of other snakes? [I.A.S. (Pre) 2008]

Correct Answer: (d) King Cobra
Solution:The king cobra’s diet consists primarily of other snakes, including rat snakes, small pythons and even other venomous snakes such as various members of the true cobras and the kraits. When food is scarce, they may also feed on other small vertebrates, such as lizards, birds, and rodents.

43. Which snake of the following is nonpoisonous? [M.P.P.C.S. (Pre) 2012]

Correct Answer: (d) Python
Solution:The Pythonidae, commonly known as pythons, are a family of nonvenomous snakes found in Africa, Asia and Australia. Among its members are some of the largest snakes in the world.

44. Poison gland of snakes is homologous to— [I.A.S. (Pre) 1993]

Correct Answer: (d) Salivary gland of vertebrates
Solution:Poison gland of snakes is homologous to salivary glands of vertebrates. Snake venom is actually the refined form of its saliva. The poison glands of snakes are believed to be modified parotid salivary glands, which are found in other vertebrates as well.

This suggests a common ancestor where these glands were used for saliva production, and in snakes, they evolved to produce venom.

Snake venom and saliva share some basic chemical components, like proteins and enzymes. The key difference is that venom has evolved to include more toxic enzymes or proteins, making it lethal to prey.

While saliva in most vertebrates aids in digestion and lubrication, snake venom serves a different purpose: defense, prey immobilization, and even digestion of prey after capture.

45. Poisonous fangs of a snake are modified form of: [U.P. R.O./A.R.O. (Pre) 2016]

Correct Answer: (d) Maxillary teeth
Solution:Poisonous fangs of a snake are modified form of maxillary teeth. There are 1-3 pairs (usually 1 pair) of long, curved, sharp and pointed maxillary teeth attached to the poison glands of the upper jaw of a snake.

46. Consider the following statements: [I.A.S. (Pre) 2019]

  1. Some species of turtles are herbivores.
  2. Some species of fish are herbivores.
  3. Some species of marine mammals are herbivores.
  4. Some species of snakes are viviparous.
    Which of the statements given above are correct?
Correct Answer: (d) 1, 2, 3 and 4
Solution:When green sea turtle (Chelonia mydas) becomes adult it becomes strictly herbivores. Many species of fish are herbivores, like parrot fish which eats algae. Some marine mammals like dugong are herbivores.

Some species of snakes like green anaconda are viviparous meaning they give birth live young ones rather than laying eggs like other reptiles. Hence, option (d) is the correct answer.

47. Dogs are herbivores — [Chhattisgarh P.C.S. (Pre) 2011]

Correct Answer: (b) False
Solution:The dog is not a herbivorous animal. The assumption that dogs are natural omnivores remains to be proven, whereas the truth about dogs being natural carnivores is very well-supported by the evidence available to us.

48. The largest flower in the world is — [U.P.P.C.S. (Pre) 1998 ,39th B.P.S.C. (Pre) 1994]

Correct Answer: (c) Rafflesia 
Solution:Rafflesia plant with no leaves, no roots, no stem is the biggest flower in the world. It sounds like the stuff of comic books or science fiction.

‘It is perhaps the largest and most magnificent flower in the world’ was how Sir Stamford Raffles described his discovery in 1818 of Rafflesia Arnoldii, modestly named after himself and his companion, surgeon-naturalist Dr. James Arnold.

49. Insectivorous plants grow in soil deficient in — [67th B.P.S.C. (Pre) 2022]

Correct Answer: (c) Nitrogen
Solution:Insectivorous plants grow in nitrogen-deficient soil and fulfill their nitrogen requirement by trapping small insects. Insectivorous plants are especially adapted for capturing and digesting insects and other animals by means of ingenious pitfalls and traps.

50. Which one of the following is an insectivorous plant? [I.A.S. (Pre) 2008]

Correct Answer: (b) Pitcher plant
Solution:A pitcher plant is a carnivorous plant or an insectivorous plant. Carnivorous plants are plants that eat insects and other small animals. Carnivorous plants grow in a soil that has less nitrogen. All living things must have nitrogen. Carnivorous plants get nitrogen from the insects they eat.