441: When ants bite, they inject
(a) glacial acetic acid
(b) methanol
(c) formic acid
(d) stearic acid
Explanation:
The pain caused during ant's bite is due to injection of Formic acid (HCOOH).
442: Due to improper/indiscriminate disposal of old and used computers or their parts, which of the following are released into the environment as e-waste?
1. Beryllium
2. Cadmium
3. Chromium
4. Heptachlor
5. Mercury
6. Lead
7. Plutonium
Select the correct answer using codes given below.
(a) 1, 2, 3, 5 and 6 only
(b) 2, 4, 5 and 7 only
(c) 1, 3, 4, 6 and 7 only
(d) 1, 2, 3, 4, 5, 6 and 7
Explanation:
Heptachlor is an insecticide.
Plutonium is radioactive which is not used in day to day computer / electronic items.
If we eliminate these two, we get our answer
443: Phenylketonuria is an example of an in born error of metabolism. This error refers to
(a) hormonal overproduction
(b) atrophy of endocrine glands
(c) inherited lack of an enzyme
(d) non-disjunction
444: Other than resistance to pests, what are the prospects for which genetically engineered plants have been created?
1. To enable them to withstand drought
2. To increase the nutritive value of the produce
3. To enable them to grow and do photosynthesis in spaceships and space stations
4. To increase their shelf life
Select the correct answer using the codes given below :
(a) 1 and 2 only
(b) 3 and 4 only
(c) 1, 2 and 4 only
(d) 1, 2, 3 and 4
Explanation:
Statement 3 is useless, rest are correct.
445: Which one of the following is a useful functional association between fungi and the roots of higher plants ?
(a) Biofertilizer
(b) Coralloid root
(c) Lichen
(d) Mycorrhiza
Explanation:
Mycorrhiza associated with the roots of higher plants. Vesicular Arbuscular Mycorrhiza (VAM) fungi are obligate symbionts penetrate the roots in host plants and form vesicles and arbuscles, reported to increase the uptake of phosphorous Zn, Cu, Mn and Fe.