31. Which statement is true about Passive Immunity?
[A] This immunity causes reactions
[B] This immunity develops immediately
[C] This immunity lasts only for a few weeks or months
[D] All of the above
Show Answer
Correct Answer: D [All of the above]
Notes:
Passive immunity is conferred when a person is given antibodies to a disease rather than produced through their own immune system. A newborn baby receives passive immunity from its mother through the placenta.
32. What is the enzyme that breaks down lactose?
[A] Lipase enzymes
[B] Pepsin
[C] Amylase
[D] Lactase
Show Answer
Correct Answer: D [Lactase]
Notes:
Lactase is the enzyme that breaks down lactose.
33. A tube that allows urine to pass out of the body __
[A] penis
[B] urethra
[C] scrotum
[D] All of the above
Show Answer
Correct Answer: B [urethra]
Notes:
A tube that allows urine to pass out of the body’s urethra. It is a long tube that runs through the penis.
34. Which of the following is the case with codominance products?
[A] Produced from both the alleles
[B] Produced from one allele
[C] Incompletely produced from both alleles
[D] None are functional
Show Answer
Correct Answer: A [Produced from both the alleles]
Notes:
In the case of codominance, the product is formed from both the alleles. It is expressed in its completeness and no allele dominates the other.
35. Bacteria protect themselves from viruses by fragmenting viral DNA?
[A] Ligase
[B] Endonuclease
[C] Exonuclease
[D] Gyrase
Show Answer
Correct Answer: C [Exonuclease]
Notes:
Bacteria protect themselves from viruses by fragmenting viral DNA with Exonuclease. Enzymes that work by cleaving one nucleotide at a time from the end (Exo) of the polynucleotide chain are called exonucleases.
36. Leptospirosis is a disease caused by ____:
[A] Fungus
[B] Protozoa
[C] Virus
[D] Bacteria
Show Answer
Correct Answer: D [Bacteria]
Notes:
Leptospirosis is a bacterial disease caused by corkscrew-shaped bacteria called Leptospira. Signs and symptoms can range from none to mild such as headaches, muscle pains, and fevers; to severe with bleeding from the lungs or meningitis. If the infection causes the person to turn yellow, have kidney failure and bleeding, it is then known as Weil’s disease.
37. ____ being a higher category, is the assemblage of families which exhibit a few similar characters:
[A] Class
[B] Species
[C] Genus
[D] Order
Show Answer
Correct Answer: D [Order]
Notes:
Order is an assemblage of families which exhibit a few similar characters. The similar characters are less in number as compared to different genera included in a family. A class includes one or more orders.
38. Saprophytes are the organisms which depend for food on
____:
[A] Inorganic chemical compounds
[B] Living plants
[C] Living animals
[D] Dead and decaying material
Show Answer
Correct Answer: D [Dead and decaying material]
Notes:
Saprophytes are the organisms which depend for food on dead and decaying material. They secrete digestive substances into the surrounding environment and break down the organic matter into simpler substances. The nutrients thus produced are absorbed directly through the cell membranes of the organisms.
39. Which of the following bacterium causes crown gall disease in plants?
[A] Agrobacterium tumefaciens
[B] Pseudomonas fluorescens
[C] Bacillus thurigiensis
[D] None of the above
Show Answer
Correct Answer: A [Agrobacterium tumefaciens]
Notes:
Crown gall is a disease caused by the bacterium Agrobacterium tumefaciens (synonym Rhizobium radiobacter), which enters the plant through wounds in roots or stems and stimulates the plant tissues to grow in a disorganized way, producing swollen galls. As the disease progresses, plants lose vigour and may eventually die. In science of Biotechnology, it is considered as natural engineer.
40. Riboflavin present in fish is also known in form of ____:
[A] Vitamin K
[B] Vitamin C
[C] Vitamin B2
[D] Vitamin B12
Show Answer
Correct Answer: C [Vitamin B2]
Notes:
Riboflavin is also known as vitamin B2. It is a vitamin found in food and used as a dietary supplement. Food sources include eggs, green vegetables, milk and other dairy product, meat, fish, mushrooms, and almonds. Riboflavin is a water soluble and heat-stable vitamin that the body uses to metabolize fats, protein, and carbohydrates into glucose for energy.
