31. The root nodules for nitrogen fixation of a non-legume tree are?
[A] Frankia
[B] Rhizobium
[C] Azotobacter
[D] Thiobacillus
Show Answer
Correct Answer: A [Frankia]
Notes:
The root nodules for nitrogen fixation of a non-legume tree are Frankia. It is a genus of nitrogen-fixing bacteria that live in symbiosis with actinorhizal plants.
32. Which chemical is used to obtain a precipitate of pure DNA?
[A] Methanol
[B] Ether
[C] HCl
[D] Ethanol
Show Answer
Correct Answer: D [Ethanol]
Notes:
Ethanol is used to obtain a precipitate of pure DNA. Renewable fuel made from corn and other plant materials is called ethanol.
33. What is the function of a polymerase chain reaction?
[A] catalyze the joining (ligation) of two large molecules
[B] amplify pieces of DNA
[C] Both 1 and 2
[D] Neither 1 nor 2
Show Answer
Correct Answer: B [amplify pieces of DNA]
Notes:
A polymerase chain reaction is a chemical reaction used by molecular biologists to amplify fragments of DNA.
34. Epidermal cells of which part of plant often secrete a waxy water resistant layer on their outer surface?
[A] Aerial parts only
[B] Roots only
[C] Both aerial parts and roots
[D] Neither aerial parts nor roots
Show Answer
Correct Answer: A [Aerial parts only]
Notes:
The major role of epidermis is to protect all the parts of the plant. Epidermal cells on the aerial parts of the plant often secrete a waxy, water-resistant layer on their outer surface. This aids in protection against loss of water, mechanical injury and invasion by parasitic fungi.
35. In coriander, the useful parts are
____:
[A] Leaves & flowers
[B] Flowers & dried fruits
[C] Roots & leaves
[D] Leaves & dried fruits
Show Answer
Correct Answer: D [Leaves & dried fruits]
Notes:
Coriander (Coriandrum sativum), also known as cilantro, Chinese parsley or dhania, is an annual herb in the family Apiaceae. All parts of the plant are edible, but the fresh leaves and the dried seeds are the parts most traditionally used in cooking.
36. Which of the following cell organelle contains DNA apart from nucleus?
[A] Golgi Apparatus
[B] Mitochondria
[C] Cytoplasm
[D] Ribosome
Show Answer
Correct Answer: B [Mitochondria]
Notes:
The three organelles that contain DNA are the nucleus, mitochondria and chloroplasts. Mitochondria are unlike most organelles (with an exception of plant chloroplasts) in that they have their own set of DNA and genes that encode proteins. They are specialized structures unique to the cells of animals, plants and fungi.
37. Intestinal bacteria synthesizes which of the following in the human body?
[A] Vitamin D
[B] Vitamin K
[C] Proteins
[D] Fats
Show Answer
Correct Answer: B [Vitamin K]
Notes:
Vitamin K is synthesized by bacteria in the intestinal tract of man and most animals in quantities sufficient to meet their needs. Besides, intestinal bacteria may also synthesize Vitamin B such as Thiamine (B1), Riboflavin (B2), Niacin (B3), Pantothenic Acid (B5), Pyroxidine (B6), and Biotin (B7), Folic Acid (B9) and Cobalamin (B12).
38. Approximate life span of parrot is ____:
[A] 20 years
[B] 40 years
[C] 70 years
[D] 140 years
Show Answer
Correct Answer: A [20 years]
Notes:
The life span of a parrot depends on the species. Smaller types of parrots generally have a life span of 15 to 20 years, while some larger varieties can live up to 120 years. The amount of time that a parrot lives greatly depends on its species, level of care, and overall health. It is not a rare occurrence for a pet parrot to outlive its owner.
39. Which is the effect of antigen in an ill person?
[A] It increases the production of antibiotics
[B] It increases the production of W.B.C.
[C] It increases the production of anti-serum against bacteria
[D] It prevents the growth of bacteria
Show Answer
Correct Answer: A [It increases the production of antibiotics]
Notes:
Vaccines containing antigens are introduced into the body, stimulating the immune system response by instructing B cells, with assistance from T cells, to produce antibodies. Antibodies are produced to fight the weakened or dead viruses in the vaccine. The immune system prepares to destroy real and stronger viruses in the future. When new antigens enter the body, white blood cells called macrophages engulf them; process the information contained in the antigens, and send it to the T cells to mobilise immune system. Hence, introduction of antigens in any form in body induces the production of antibodies to boost immunity.
40. Red rot is a disease caused to which of the following plant?
[A] Sugarcane
[B] Wheat
[C] Paddy
[D] Mustard
Show Answer
Correct Answer: A [Sugarcane]
Notes:
Red rot is one of the oldest known diseases of sugarcane that is caused by the fungus Colletotrichum falcatum (Glomerella tucumanensis). It is characterized by interrupted red and white patches within the cane along with a sour alcoholic odour when the cane is split open.
