16)The digestive juice that lacks enzymes but helps digestion is
chyle chyme
bile none of these
Answer :

17) The wavelength of light most effective in photosynthesis is
green red
blue yellow
Answer :

18) The carbon of organic compounds in plants comes from
organic compounds absorbed from the soil atmospheric carbondioxide
carbonates absorbed from soil none of these
Answer :

19)Green plants gives out oxygen during day time rather than carbon dioxide. This means
green plants do not respire green plants respire only at night
rate of photosynthesis is higher than that of respiration respiration rate of green plants is much lower during day time
Answer :

20)Which of the following animals can bring oxygen directly to the cell?
spider insects
scorpion flatworm
Answer :

21)One should not sleep under a tree at night because of
release of less oxygen release of carbon monoxide
release of carbondioxide release of more oxygen
Answer :

22)The digestive and breathing passages cross in the
larynx pharynx
trachea none of these
Answer :

23)In milk fat content is reduced during
summer winter
monsoon none of these
Answer :

24)Consumption of Kesari dal is banned because it causes gradual loss of
movement of lower limbs hearing
vision white blood cells
Answer :

25)The life span of human red corpuscles is
180 days 100 days
120 days equal to the life of the person
Answer :

26)The average rate of heart beats in an adult is
60 per minute 72 per minute
82 per minute 86 per minute
Answer :

27)The role of root hair in plants is
to bind the soil particles to the root for firm fixation of the plant to protect the root from damage by coarse soil particles
to absorb water and minerals from the soil none of these
Answer :

28) The volume of a paste of rice or wheat increases if kept open for a night due to
bacterial growth absorption of water by the particles of the paste
the release of carbon dioxide from the yeast activity oxidation of the paste
Answer :

29)The principle on which artificial kidney operates is
osmosis active transport
diffusion dialysis
Answer :

30)The colour of human eyes is determine by the pigment present in the
choroid cornea
iris vitreous body
Answer :