Biology

61. In the context of vaccines manufactured to prevent COVID-19 pandemic,

In the context of vaccines manufactured to prevent COVID-19 pandemic, consider the following statements:

  • The Serum Institute of India produced COVID-19 vaccine named Covishield using mRNA platform.
  • Sputnik V vaccine is manufactured using vector based platform.
  • COVAXIN is an inactivated pathogen based vaccine.

Which of the statements given above are correct ?

[amp_mcq option1=”1 and 2 only” option2=”2 and 3 only” option3=”1 and 3 only” option4=”1, 2 and 3″ correct=”option2″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
Statements 2 and 3 are correct. Statement 1 is incorrect.
– Statement 1 is incorrect: Covishield, manufactured by the Serum Institute of India, is the Oxford-AstraZeneca vaccine. It uses a viral vector platform (specifically, a modified chimpanzee adenovirus) to deliver the genetic material for the SARS-CoV-2 spike protein. It is not an mRNA vaccine.
– Statement 2 is correct: Sputnik V, developed by the Gamaleya Research Institute in Russia, is an adenoviral vector vaccine. It uses two different human adenoviruses (Ad26 and Ad5) for the two doses.
– Statement 3 is correct: COVAXIN, developed by Bharat Biotech in India, is an inactivated pathogen-based vaccine. It uses the whole SARS-CoV-2 virus, which has been chemically inactivated so it cannot replicate or cause disease, but can still trigger an immune response.
COVID-19 vaccines utilize various platforms, including mRNA (e.g., Pfizer-BioNTech, Moderna), viral vector (e.g., AstraZeneca/Covishield, Sputnik V, Johnson & Johnson), inactivated virus (e.g., COVAXIN, Sinovac, Sinopharm), and protein subunit. Understanding the platform is key to knowing how the vaccine works.

62. Consider the following statements in respect of probiotics : Probiot

Consider the following statements in respect of probiotics :

  • Probiotics are made of both bacteria and yeast.
  • The organisms in probiotics are found in foods we ingest but they do not naturally occur in our gut.
  • Probiotics help in the digestion of milk sugars.

Which of the statements given above is/are correct ?

[amp_mcq option1=”1 only” option2=”2 only” option3=”1 and 3″ option4=”2 and 3″ correct=”option3″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
Statements 1 and 3 are correct, while statement 2 is incorrect.
– Statement 1 is correct: Probiotics are typically defined as live microorganisms which, when administered in adequate amounts, confer a health benefit on the host. While many probiotics contain bacteria (e.g., Lactobacillus, Bifidobacterium), some also include yeasts (e.g., Saccharomyces boulardii). Thus, probiotics can be made of bacteria, yeast, or a combination of both.
– Statement 2 is incorrect: The beneficial organisms used in probiotics, such as various species of Lactobacillus and Bifidobacterium, are natural inhabitants of the human gut microbiome. Probiotics are consumed to supplement or enhance these populations.
– Statement 3 is correct: Some probiotic strains, particularly certain bacteria like Lactobacillus species, produce the enzyme beta-galactosidase (lactase), which helps break down lactose (milk sugar). This can aid in the digestion of milk sugars, especially for individuals with lactose intolerance.
The effectiveness of probiotics is strain-specific and depends on the specific health condition being targeted. Probiotic research is ongoing, exploring benefits for various conditions including digestive health, immune function, and mental well-being.

63. Consider the following statements : Biofilms can form on medical imp

Consider the following statements :

  • Biofilms can form on medical implants within human tissues.
  • Biofilms can form on food and food processing surfaces.
  • Biofilms can exhibit antibiotic resistance.

Which of the statements given above are correct ?

[amp_mcq option1=”1 and 2 only” option2=”2 and 3 only” option3=”1 and 3 only” option4=”1, 2 and 3″ correct=”option4″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
All three statements regarding biofilms are correct.
– Statement 1 is correct: Biofilms are a significant cause of infections on medical implants like catheters, prosthetic joints, and heart valves, as bacteria can attach to the surface and form a protective layer.
– Statement 2 is correct: Biofilms readily form on surfaces in food processing environments and on the food itself, leading to spoogenic (spoilage-causing) and pathogenic contamination.
– Statement 3 is correct: Biofilms provide microorganisms with increased resistance to antibiotics, disinfectants, and the host immune system. This is due to the protective matrix, altered growth rates of cells within the biofilm, and genetic exchange.
Biofilms are complex communities of microorganisms encased in a self-produced extracellular matrix. They can adhere to various surfaces, both living and non-living, and are ubiquitous in many environments, posing challenges in healthcare, food safety, and industrial settings.

64. Which of the following are nitrogen-fixing plants ? Alfalfa Amarant

Which of the following are nitrogen-fixing plants ?

  1. Alfalfa
  2. Amaranth
  3. Chickpea
  4. Clover
  5. Purslane (Kulfa)
  6. Spinach

Select the correct answer using the code given below :

[amp_mcq option1=”1, 3 and 4 only” option2=”1, 3, 5 and 6 only” option3=”2, 4, 5 and 6 only” option4=”1, 2, 4, 5 and 6″ correct=”option1″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
The nitrogen-fixing plants among the given options are Alfalfa, Chickpea, and Clover.
– Nitrogen fixation is the process by which atmospheric nitrogen (N₂) is converted into ammonia (NH₃) or related nitrogenous compounds. In agriculture, this is primarily done by bacteria, notably Rhizobia, which live symbiotically in the root nodules of leguminous plants.
– Alfalfa (Medicago sativa) is a legume and fixes nitrogen.
– Amaranth (Amaranthus spp.) is not a legume and does not fix nitrogen.
– Chickpea (Cicer arietinum) is a legume and fixes nitrogen.
– Clover (Trifolium spp.) is a legume and fixes nitrogen.
– Purslane (Kulfa) (Portulaca oleracea) is not a legume and does not fix nitrogen.
– Spinach (Spinacia oleracea) is not a legume and does not fix nitrogen.
Nitrogen-fixing plants play a crucial role in natural ecosystems and agriculture by increasing soil fertility. They are often used in crop rotation and as cover crops. While legumes are the most common examples of symbiotic nitrogen fixers, certain other plants (like Alnus) also host nitrogen-fixing bacteria (like Frankia).

65. Which of the following is not a bird ?

Which of the following is not a bird ?

[amp_mcq option1=”Golden Mahseer” option2=”Indian Nightjar” option3=”Spoonbill” option4=”White Ibis” correct=”option1″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
Golden Mahseer is not a bird.
– Golden Mahseer (Tor putitora) is a species of fish, found in the Himalayan region.
– Indian Nightjar (Caprimulgus indicus) is a species of bird.
– Spoonbill is the common name for birds in the subfamily Plataleinae, known for their distinct spatulate beaks.
– White Ibis is the common name for several species of birds in the genus Eudocimus, belonging to the family Threskiornithidae (ibises and spoonbills).
The question requires basic knowledge of common animal names and classification. Identifying the Golden Mahseer as a fish readily distinguishes it from the other options, which are all birds.

66. With reference to “Gucchi” sometimes mentioned in the news, consider t

With reference to “Gucchi” sometimes mentioned in the news, consider the following statements:

  • 1. It is a fungus.
  • 2. It grows in some Himalayan forest areas.
  • 3. It is commercially cultivated in the Himalayan foothills of north-eastern India.

Which of the statements given above is/are correct ?

[amp_mcq option1=”1 only” option2=”3 only” option3=”1 and 2″ option4=”2 and 3″ correct=”option3″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
The correct option is C, as statements 1 and 2 are correct.
Statement 1 is correct. Gucchi (Morchella esculenta) is a type of wild mushroom, which belongs to the kingdom Fungi.
Statement 2 is correct. Gucchi is a highly valued edible fungus that grows wild in certain Himalayan forest areas, particularly in states like Jammu and Kashmir, Himachal Pradesh, and Uttarakhand, usually after the snow melts.
Statement 3 is incorrect. Gucchi is extremely difficult to cultivate commercially due to its complex growth cycle, which is not fully understood. It is primarily collected from the wild, making it expensive and rare. While research into its cultivation is ongoing, it is not commercially cultivated on a significant scale, especially not widely in the Himalayan foothills of north-eastern India (which is less known for Gucchi compared to the western Himalayas).
Gucchi mushrooms are prized for their unique flavour and texture and are one of the most expensive fungi globally. Their rarity is largely due to the inability to cultivate them reliably and their unpredictable appearance in the wild.

67. Certain species of which one of the following organisms are well known

Certain species of which one of the following organisms are well known as cultivators of fungi?

[amp_mcq option1=”Ant” option2=”Cockroach” option3=”Crab” option4=”Spider” correct=”option1″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
Certain species of ants are well known for cultivating fungi for food.
Ants belonging to the tribe Attini (found in the Americas), particularly leafcutter ants, are famous examples of organisms that cultivate fungi. They create fungal gardens using collected plant material (like leaves) as substrate, on which specific fungi grow. The ants then feed on the fungal mycelium. This represents a sophisticated form of symbiosis.
While other insects like termites and some beetles also cultivate fungi, among the options provided, ants are the most widely known examples of fungus cultivators. Cockroaches, crabs, and spiders do not typically cultivate fungi in this manner.

68. Consider the following statements : DNA Barcoding can be a tool to :

Consider the following statements :
DNA Barcoding can be a tool to :

  • assess the age of a plant or animal
  • distinguish among species that look alike.
  • identify undesirable animal or plant materials in processed foods.

Which of the statements given above is/are correct ?

[amp_mcq option1=”1 only” option2=”3 only” option3=”1 and 2″ option4=”2 and 3″ correct=”option4″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
The correct answer is D) 2 and 3.
Statement 1 is incorrect. DNA barcoding is a method for identifying species using a short, standardized sequence of DNA. It provides a “barcode” that is unique to a species, but it does not provide information about the age of an individual plant or animal.
Statement 2 is correct. DNA barcoding is highly effective at distinguishing among species, even those that are morphologically similar or difficult to identify using traditional methods. The barcode sequence provides a clear genetic signature for differentiation.
Statement 3 is correct. DNA barcoding can be used to identify the species composition of biological materials in processed foods, allowing detection of adulteration, mislabeling, or the presence of undesirable or allergenic plant or animal materials.
The standard barcode region used for animals is a segment of the mitochondrial gene cytochrome c oxidase subunit I (COI). For plants, different regions are used, such as rbcL and matK in chloroplast DNA. DNA barcoding has applications in biodiversity studies, food safety, forensic science, and wildlife trafficking detection.

69. Which one of the following statements best describes the role of B cel

Which one of the following statements best describes the role of B cells and T cells in the human body ?

[amp_mcq option1=”They protect the body from environmental allergens.” option2=”They alleviate the body’s pain and inflammation.” option3=”They act as immunosuppressants in the body.” option4=”They protect the body from the diseases caused by pathogens.” correct=”option4″]

This question was previously asked in
UPSC IAS – 2022
Download PDFAttempt Online
The correct answer is D) They protect the body from the diseases caused by pathogens.
B cells and T cells are lymphocytes, which are key components of the adaptive immune system. Their primary role is to recognize specific pathogens (like bacteria, viruses, fungi, and parasites) and mount a targeted immune response to eliminate them and prevent diseases.
B cells produce antibodies that neutralize pathogens or mark them for destruction. T cells directly kill infected cells (cytotoxic T cells), help other immune cells (helper T cells), or regulate the immune response (regulatory T cells).
While immune responses involving B and T cells can contribute to inflammation (which is part of healing but also causes pain), their main function is not to alleviate pain or inflammation directly (Option B). They are crucial for developing immunity, not immunosuppression (Option C), though certain subsets of T cells are regulatory. While they are involved in responses to allergens, their role in protecting against pathogens is their fundamental and primary function (Option A vs. D).

70. The term ‘ACE2’ is talked about in the context of

The term ‘ACE2’ is talked about in the context of

[amp_mcq option1=”genes introduced in the genetically modified plants” option2=”development of India’s own satellite navigation system” option3=”radio collars for wildlife tracking” option4=”spread of viral diseases” correct=”option4″]

This question was previously asked in
UPSC IAS – 2021
Download PDFAttempt Online
The term ‘ACE2’ stands for Angiotensin-converting enzyme 2. This enzyme is a protein found on the surface of many cells, particularly in the lungs, heart, kidneys, and intestines. It became widely known because it serves as the primary receptor that the SARS-CoV-2 virus (which causes COVID-19) uses to enter human cells. Therefore, ACE2 is talked about extensively in the context of the spread of viral diseases, specifically COVID-19.
– ACE2 is a protein enzyme found on cell surfaces.
– It acts as a receptor for coronaviruses, including SARS-CoV-2.
– The binding of the virus to ACE2 is the initial step in cellular infection.
ACE2 is part of the renin-angiotensin system (RAS), which plays a crucial role in regulating blood pressure and fluid balance. Research is ongoing to understand the complex interaction between SARS-CoV-2 and ACE2, and how it affects the RAS and contributes to the severity of COVID-19 disease.
Page 1Page 2Page 3Page 4Page 5
Exit mobile version