456: Amniocentesis is a method for:
(a) Determination of foetal sex.
(b) Separation of amino acids.
(c) Determination of the sequence of amino acids in a protein.
(d) Inducing abortion.
457: Which of the following types is used by computed tomography employed for visualization of the internal structure of human body ?
(a) Magnetic resonance
(b) X-rays
(c) sound Waves
(d) Radioisotopes
Explanation:
Computed tomography (CT) is a powerful nondestructive evaluation (NDE) technique for producting 2-D and 3-D cross-sectional images of images of an object from flat X-ray images.
458: Consider the following organisms:
1. Agaricus
2. Nostoc
3. spirogyra
Which of the above is/are used as biofertilizer/biofertilizers?
(a) 1 and 2
(b) 2 only
(c) 2 and 3
(d) 3 only
Explanation:
A biofertilizer (also bio-fertilizer) is a substance which contains living microoganisms which, when applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the niterior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant. Bio-fertilizers add nutrients through the natural processes of nitrogen fixation,soliloquizing phosphorus, and stimulating plant growth through the synthesis of growth-promoting substances.
Bio-fertilizers such as Nostoc or Anabaena or Tolypothrix or Aulosira, fix atmospheric nitrogen and are used as inoculations for paddy crop grown both under upland and low-land conditions.
Agaricus is a genus of mushrooms containing both edible and poisonous species, with possibly over 300 members worldwide. Spirogyra is a green algea. Hence, both 2 and 3 are not biofertilizers.
459: Consider the following statements :
Glass can be etched or scratched by
I. diamond.
II. hydrofluoric acid.
III. aquaregia.
IV. cone, sulphuric acid.
Which of these statements are correct ?
(a) I and IV
(b) II and III
(c) I and II
(d) II and IV
Explanation:
Diamond is the hardest element on the earth and is used to cut or scratch glass whereas hydrofluoric acid is used for writing on the glass.
460: Which of the following adds/add nitrogen to the soil?
1. Excretion of urea by animals
2. Burning of coal by man
3. Death of vegetation
Select the correct answer using the codes given below.
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
Explanation:
Nitrogenous Waste products of animals are urea and uric acid.
Dead remains of organisms are converted back to inorganic ammonia by the bacteria.
So option 1 and 3 is correct.