Biology (Part-II) (UPSC)

Total Questions: 50

21. What is the average fat content of buffalo milk? [1997]

Correct Answer: (a) 7.2%
Solution:Average fat content in buffalo milk is 7.2% and average fat content in cow milk is 4.4%. As per the nutrient components, buffalo milk contains all the nutrients in higher proportion than cow's milk
Although buffalo milk is not common in many parts of the world, it represents 11% of global milk production, second to cows.7 Pakistan and India are the major producers and consumers of buffalo milk. Although it is uncommon in Europe, buffalo's milk is of great importance in several Mediterranean cultures where it is utilized in making traditional mozzarella cheese.
Similar to the other types of milk already discussed, the microbial constitution milk from buffaloes shows a dominance by LAB. Nonetheless, this type of milk also contains pathogenic microorganisms such as E. coli, Staphylococcus aureus, and coliforms. DGGE techniques have also been employed in the analysis of the microbial composition of buffalo milk, highlighting the significant diversity of microbiota

22. The major component of honey is : [1997]

Correct Answer: (d) fructose
Solution:The major component of honey is fructose. Composition of honey in (percentage) :

Fructose : 38.2, Glucose : 31, Water : 17.1, Carbohydrate : 4.2, Sucrose : 1.5, Minerals : 0.5, Maltose : 7.2 .

23. Arteries supplying blood to the heart are called : [1997]

Correct Answer: (c) Coronary arteries
Solution:Coronary arteries supply blood to heart. Carotid arteries supply the blood to head region. Hepatic arteries supply to liver and pulmonary arteries supplies blood to the lungs.
Arteries, a critical part of your cardiovascular system, are blood vessels that distribute oxygen-rich blood to your entire body. These tube-like vessels and the muscles inside them ensure your organs and tissues have the oxygen and nutrients they need to function. A condition called atherosclerosis can slow down blood flow through your arteries.

24. Daily intake of proteins, recommended for a moderately active woman is : [1997]

Correct Answer: (d) 46 g
Solution:Daily intake of protein for active woman is 46 gram. But at pregnant women the protein requirement increase to 47-60 gm per day.

Active means a lifestyle that includes physical activity equivalent to walking more than 3 miles per day at 3 to 4 miles per hour, in addition to the light physical activity associated with typical day-to-day life.

25. Match List-I with List-II and select the correct answer by using the codes given below: [1997]

List-IList-II 
A. Malaria1. Bone marrow
B. Filaria2. Brain
C. Encephalitis3. Muscle
D. Leukaemia4. Lymph node
5. Blood cells

Codes:

ABCD
(a) 5321
(b)5421
(c)4351
(d)5412
Correct Answer: (b)
Solution:Malaria is the parasitic disease spreads through the sucking of blood through mosquitoes. The malaria parasite invades blood cells.

The virus of encephalitis most active in brains. Filaria parasite found in blood lymph and leukaemia is cancer mainly the abnormal cell growth in bone narrow.

26. Antigen is a substance which : [1997]

Correct Answer: (c) triggers the immune system
Solution:Antigen is a foreign molecule that invade the body of an organism. Antigen also induce immune response to stimulate lymphocyte to produce antibody. The majority of them are proteins and polysaccharides found on the wall of bacteria and on the cell coats of virus.

27. The sequencing of the entire genome (the totality of all genes) of an organism was completed in 1996. The organism was: [1997]

Correct Answer: (b) yeast
Solution:The sequencing of the entire genome of yeast was completed in 1996.

Whole-genome sequencing (WGS) is a comprehensive method for analyzing entire genomes. Genomic information has been instrumental in identifying inherited disorders, characterizing the mutations that drive cancer progression, and tracking disease outbreaks. Genes account for less than 25 percent of the DNA in the genome, and so knowing the entire genome sequence will help scientists study the parts of the genome outside the genes. This includes the regulatory regions that control how genes are turned on an off, as well as long stretches of "nonsense" or "junk" DNA.

28. Examine the following three statements: [1998]

1. Processed meat is a perishable food

2. All perishable foods are packed in sealed tins

3. Sealed tins sometimes do not contain processed meat

Which one of the following inferences can be drawn from the above statements?

Correct Answer: (c) Processed meat is always packed in sealed tins
Solution:We can draw the inference that processed meat is always packed in sealed tins.

29. Match List-I with List-II and select the correct answer using the codes given below the lists: [1998]

List-I List-II 
A. Theory of mutation1. Beadle and Tatum
B. Theory of evolution2. Jacob and Monad
C. One gene one enzyme hypothesis3. Darwin
D. Operon concept4. de Vries

Codes:

ABCD
(a)3412
(b)4312
(c)4321
(d)3421
Correct Answer: (b)
Solution:
  • Theory of mutation was proposed by the Dutch botanist Hugo de Vries in the early 20th century. He suggested that new species arose from sudden, large changes, which he called mutations.
  • Theory of evolution by natural selection was formulated by Charles Darwin, as detailed in his book On the Origin of Species in 1859.
  • The One gene one enzyme hypothesis was proposed by George Beadle and Edward Tatum in the 1940s, based on their experiments with the mold Neurospora crassa. This hypothesis stated that each gene is responsible for producing a single enzyme.
  • The Operon concept, a model for gene regulation in bacteria, was proposed by François Jacob and Jacques Monod in 1961.

30. A tree species in Mauritius failed to reproduce because of the extinction of a fruit-eating bird. Which one of the following was that bird? [1998]

Correct Answer: (b) Dodo
Solution:Dodo birds species existed only on the island of Mauritius. Due to its short wings and bulky body the Dodo birds could not fly or flee in the face of danger.

So human used to kill them for food. Later the species became extinct from Mauritius. This bird species was helpful in pollinating and propagating seed of trees.