Biology (Part-III) (UPSC)

Total Questions: 50

31. Consider the following statements: [2004]

1. Toothless mammals such as Pangolins are not found in India.

2. Gibbon is the only ape found in India.

Which of the statements given above is/are correct?

Correct Answer: (b) 2 only
Solution:Gibbon is the only ape found in rain forests of Assam in India, whereas Pangolins are found in tropical Asia and Africa.
• In India, it is found in Assam, Meghalaya, Arunachal Pradesh, Nagaland, Manipur, Mizoram, and Tripura, south of the Brahmaputra.
• Hollongapar Gibbon Sanctuary in Assam has the largest concentration of the hoolock gibbon.
• It is categorised into Eastern Hoolock Gibbon (Hoolock leuconedys) found in a specific region of Arunachal Pradesh and Western Hoolock Gibbon (Hoolock hoolock) distributed elsewhere in the northeast.

32. In which organ of the human body, lymphocyte cells formed? [2004]

Correct Answer: (b) Long bone
Solution:Lymphocytes are the cells that determine the specificity of the immune response to infectious microorganisms and other foreign substances. In humans lymphocytes make up 25 to 33% of the total number of leukocytes. Lymphocytes cells originate from bone marrow of long bones and Hen migrate to lymphatic system.

33. Assertion (A): Fatty acids should be a part of the balanced human diet. [2004]

Reason (R): The cells of the human body cannot synthesize any fatty acids.

Correct Answer: (c) A is true but R is false
Solution:Assertion is true because a balanced diet is a diet which contains the correct amount of carbohydrates, proteins and fats. But the reason is false, because human body cells synthesize various fatty acids except linoleic and linolenic fatty acids.

34. Consider the following statements: [2004]

1. Femur is the longest bone in the human body.

2. Cholera is a disease caused by bacteria.

3. 'Athlete's foot' is a disease caused by virus.

Which of the statements given above are correct?

Correct Answer: (a) 1 and 2
Solution:

• The femur (thigh bone) is the longest and strongest bone in the human body, extending from the hip to the knee.
• Cholera is an infectious disease of the small intestine caused by the bacterium Vibrio cholerae and typically contracted from contaminated water or food, producing severe diarrhoea and dehydration.
• “athlete’s foot” (tinea pedis) is a contagious fungal infection (dermatophytes) of the feet that thrives in warm, moist environments and is treated with antifungal agents, not a viral infection.

35. Consider the following statements: [2005]

1. Dengue is a protozoan disease transmitted by mosquitoes.

2. Retro-orbital pain is not a symptom of dengue.

3. Skin rash and bleeding from nose and gums are some of the symptoms of dengue.

Which of the statements given above is/are correct?

Correct Answer: (b) 3 only
Solution:Dengue viruses are transmitted to humans through the bites of infective female Aedes mosquito. The symptoms of disease is characterized by high fever, severe muscle pain, joint pain and rashes in body.

The Aedes aegypti mosquito is the main transmitter of dengue, Zika, chikungunya and yellow fever viruses.

36. Which of the following diseases of milching animals are infectious ? [2005]

1. Foot and mouth disease

2. Anthrax

3. Black Quarter

4. Cowpox

Select the correct answer using the codes given below:

Correct Answer: (d) 1, 2, 3 and 4
Solution:

• All four listed diseases are infectious. Foot-and-mouth disease is caused by the FMD virus and is a highly contagious viral disease of cloven-hoofed animals.
• Anthrax (referred to as “Autra” in the question) is caused by Bacillus anthracis and is an infectious bacterial disease affecting livestock and wildlife.
• Blackquarter (blackleg) is a bacterial clostridial disease listed among infectious bovine diseases in veterinary manuals and control lists.
• Cowpox is a zoonotic viral infection (related to orthopoxviruses) that infects animals and can transmit to humans, and is described as an infectious disease in clinical overviews.

37. Assertion (A): All the proteins in our food are digested in small intestine only. [2005]

Reason (R): The protein-digesting enzyme from pancreas are released into small intestine.

Correct Answer: (d) Ais false but R is true
Solution:Assertion is false because protein digestion occurs in stomach and small intestine. But reason is true because the proteolytic enzyme from pancreas secretion immediately enters to small intestine from the stomach.
• Proteins are large, complex molecules made up of long chains of amino acids. They perform a wide variety of functions in the body, including structural support, catalyzing biochemical reactions (as enzymes), transporting molecules, and defending against pathogens (as antibodies). Proteins are essential for growth, tissue repair, and maintaining proper bodily functions.
• Each protein’s structure is determined by its amino acid sequence, and the function is closely tied to its three-dimensional shape.
• The body synthesizes proteins based on genetic instructions in DNA, and they are found in all living organisms. Examples of proteins include hemoglobin, insulin, and collagen.

38. Assertion (A): Amoeba reproduces by fission. [2005]

Reason (R): All unicellular organisms reproduce by asexual methods.

Correct Answer: (a) Both A and R are individually true and R is the correct explanation of A
Solution:Assertion is correct and reason is the correct explanation of assertion.

Amoeba is a unicellular animal. It reproduce by the process of asexual reproduction. Fission is one of the processes of asexual reproduction, where amoeba divides in half to produce

39. Assertion (A): The person with Diabetes insipidus feels thirsty. [2005]

Reason (R): A person with Diabetes insipidus suffers from excess secretion of vasopressin.

Correct Answer: (c) A is true but R is false
Solution:Assertion is correct but the reason is false. Deficiency of vasopressin results Diabetes insipidus. In this disease the patients produce enormous quantities of dilute urine and the patient consequently feels thirsty.

Diabetes insipidus (water diabetes) is a rare condition caused by a reduction in, or failure to respond to, anti-diuretic hormone.

40. Pneumoconiosis affects the workers who work mainly in : [2005]

Correct Answer: (b) Coal mining industry
Solution:Pneumoconiosis is a respiratory disease caused by the inhaling various type of dust, such as coal dust, silica dust, asbestos dust etc. So, it is very common in workers of coal mining industries and related industries.
• The disease appears in different forms, depending on the type of dust you inhale. One of the most common forms is black lung disease, also known as miner’s lung. It’s caused by breathing in coal dust. Another is brown lung, which comes from working around dust from cotton or other fibers. Other types of dusts that can cause pneumoconiosis include silica and asbestos. Diacetyl, the compound used to give movie popcorn its buttery flavor, also can lead to the disease. This is known as popcorn lung.
• Pneumoconiosis can be simple or complicated. Simple pneumoconiosis causes a small amount of scar tissue. The tissue may appear on an X-ray as round, thickened areas called nodules. This type of disease is sometimes called coal worker pneumoconiosis, or CWP. Complicated pneumoconiosis is known as progressive massive fibrosis, or PMF. Fibrosis means that a lot of scarring is present in the lungs.
• For either simple or complicated pneumoconiosis, the damage causes the loss of blood vessels and air sacs in your lungs. The tissues that surround your air sacs and air passages become thick and stiff from scarring. Breathing becomes increasingly difficult. This condition is called interstitial lung disease.