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Secretion of gastric juice is stimulated by
pepsin
gastrin
renin
secretin
B.
gastrin
The flow of gastric juice is regulated partly by a nervous mechanism and partly by the action of the hormone gastrin, which is produced in the mucosa cells of the stomach. It induces the secretion of gastric juice by gastric glands.
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Which one shows bio-luminescence?
Noctiluca
Polystomella
Entamoeba
Suctoria
A.
Noctiluca
Noctiluca is a marine and pelagic dinoflagellate which shows bio-luminescence. At night, it produces the effect of burning of sea. The luminescence is caused by a bio-luminescent luciferin,which under the influence of an
enzyme luciferase emits light.
Mantle, foot and shell are the characteristics of
Nautilus
Echinus
Limulus
Euplectella
A.
Nautilus
Mantle, foot and shell are characteristics of a mollusc. Nautilus is a mollusc, it is a tetrabranch cephalopod. The shell is external and coiled over the head. Nauctilus is always active at night and rests on bottom during day.
Protists are
(i) unicellular and prokaryote
(ii) unicellular and eukaryote
(iii) multicellular and eukaryote
(iv) autotroph or heterotroph
(i), (ii) and (iii)
(ii), (iii) and (iv)
(iii), (iv)
(ii), (iv)
D.
(ii), (iv)
A five kingdom division of organisms was proposed by Whittaker. Protista is one of that division. It is a kingdom of unicellular, eukaryotic organism. Many of them are photosynthetic autotrophs, unicellular algae and diatoms. Some protists are heterotrophic, e.g. Protozoa.
Pepsin is inactivated at pH
below 3
below 2
above 5
above 3
C.
above 5
Pepsin is inactivated at pH above 5. Pepsin is a proteolytic or protein splitting enzyme. The pH optimum of pepsin is about 2 and the enzyme, therefore, works well in the acidic gastric juice while it is inactivated in the basic medium.
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Mock Test Series
