11. What is the time taken by the rashes to appear on the body of the patient after the Measles attack?
[A] One day
[B] Four days
[C] Six days
[D] One week
Show Answer
Correct Answer: B [Four days]
Notes:
Measles is a very infectious and potentially serious illness that is caused by a type of virus called paramyxovirus. It is spread from person to person by coughing, sneezing or sometimes kissing. Symptoms will usually begin to show 10 to 14 days after infection with the measles virus. A person with measles is infectious for 2-4 days before the rash appears (when there may be symptoms of fever and tiredness), and for up to 4 days after the rash has appeared.
12. Which one of the following is a fast growing tree?
[A] Teak
[B] Eucalyptus
[C] Banyan
[D] Coconut
Show Answer
Correct Answer: B [Eucalyptus]
Notes:
Eucalyptus is the fast growing tree. Most eucalyptus species have a root depth of 1.5-2.0 metre and its root system is more specifically adapted to using rain-fed soil moisture from the upper soil profile, rather than from the groundwater table at considerable depth. The plant is significant for wood availability, livelihood generation and carbon sequestration that address the challenges of global warming and climate change.
13. How does the Hybridisation develop improved crops?
[A] Creating new and better genes
[B] Eliminating undesirable genes
[C] Producing favourable combination of genes
[D] By encouraging favourable genes and removing unfavourable ones
Show Answer
Correct Answer: C [Producing favourable combination of genes]
Notes:
Hybridization is beneficial for improvement in crop production as the Hybrid variety of crops have some special characteristics like good resistance to diseases, improved yield, etc. so they are often sought to have a high production.
14. Why man cannot digest cellulose whereas cows can do so? (UPSC Prelims 1992)
[A] Their gut contains certain bacteria capable of digesting cellulose
[B] They have a many-chambered stomach
[C] They have efficient grinding molars
[D] They produce enzyme cellulose which can digest cellulose
Show Answer
Correct Answer: A [Their gut contains certain bacteria capable of digesting cellulose]
Notes:
Unlike cows for example don’t have the necessary bacteria in their intestines that make the enzymes necessary to breakdown the 1-4 beta glucose bonds. So we cannot break down cellulose into its constituent glucose molecules as we do with starch.
15. Which one of the following is a membrane that protects the developing embryo from desiccation? (UPSC Prelims 1995)
[A] Amnion
[B] Allantois
[C] Chorion
[D] Yolk sac
Show Answer
Correct Answer: A [Amnion]
Notes:
The amnion or amniotic sac protects everyone embryo from desiccation, it contains amniotic fluid which cushions the embryo from shocks.
16. Which of the following define the hormone insulin? (UPSC Prelims 2004)
[A] Glycolipid
[B] Fatty acid
[C] Peptide
[D] Stero
Show Answer
Correct Answer: C [Peptide]
Notes:
Insulin is a protein chain or peptide hormone. There are 51 amino acids in an insulin molecule. It has a molecular weight of 5808 Da. Insulin is produced in the islets of Langerhans in the pancreas.
17. Which among the following is not a fat soluble vitamin?
[A] Vitamin A
[B] Vitamin B
[C] Vitamin K
[D] Vitamin D
Show Answer
Correct Answer: B [Vitamin B]
Notes:
Vitamins are classified into two broad categories, water soluble (vitamins B complex and C) and fat soluble (vitamins A,D,E and K).
Extra info: Excess intake of fat soluble vitamins leads to toxicity and poses greater risk.
18. Which branch of biology is known for the study of plant fossils?
[A] Paleobotany
[B] Morphology
[C] Lichenology
[D] Agronomy
Show Answer
Correct Answer: A [Paleobotany]
Notes:
Paleobotany is the scientific study of ancient plants using plant fossils found in sedimentary rocks.
19. Who proposed the model for protein synthesis?
[A] Ostwald Avery
[B] Mclyn McCarthy
[C] Colin Macleod
[D] All of these
Show Answer
Correct Answer: D [All of these]
Notes:
Ostwald Avery, McLean McCarthy and Colin MacLeod proposed a model for the process of protein synthesis with the help of DNA in bacterial cells. Cell growth, synthesis of DNA, synapsis and synthesis of proteins.
20. Plants that reproduce by spores are classified into which of the following?
[A] Bryophytes
[B] Sporophytes
[C] Cryptogams
[D] Thallophytes
Show Answer
Correct Answer: C [Cryptogams]
Notes:
A cryptogam is a plant or plant-like organism that reproduces by spores without flowers or seeds.
