Soil Science - Study Mode
[#891] The behaviour of the plant in relation to day length is termed
Correct Answer
(B) Photoperiodism
Explanation
Solution: The behavior of the plant about day length is termed Photoperiodism . It is the physiological reaction of organisms to the length of the night or a dark period. Plant photoperiodism can be defined as the developmental responses of the plants to the relative lengths of light and dark periods.
[#892] Among the following, the correct sequence of biotic biopolymer degradation pathway is
Correct Answer
(B) Fulvic acid - a humic acid - a recalcitrant biopolymers - a humin acid
Explanation
Solution: Among the following, the correct sequence of biotic biopolymer degradation pathway is Fulvic acid - a humic acid - recalcitrant biopolymers- a humin acid. Microbiological degradation of synthetic biopolymers takes place through the action of enzymes and acids and peroxides secretes from bacteria, fungi, yeast, etc. saprophytic enzymes play an active role in the decomposition process of humic substances in the soil.
[#893] Browning disease of rice is a
Correct Answer
(A) Physiological disease
Explanation
Solution: Browning disease of rice is a Physiological disease. The physiological issues affect the toxicity level of iron elements which further causes browning disease of the rice. Iron toxicity occurs usually due to submerged paddy fields with low pH, leading to dramatic increases in ferrous ion concentration, disrupting cell homeostasis and impairing growth and yield.
[#894] Limonite is the source of
Correct Answer
(D) Fe
Explanation
Solution: Limonite is an iron ore consisting of a mixture of hydrated iron oxide hydroxides in varying compositions. It is relatively dense with a specific gravity varying from 2.7 to 4.3. It is usually medium to dark yellowish-brown in colour. In its brown form, it is sometimes called brown haematite or brown iron ore.
[#895] Which one is the most important among Amphibloes
Correct Answer
(A) Hornblend
Explanation
Solution: Amphiboles are a group of rock-forming minerals. Hornblende is the most common and most important amphibole in soil formation. It's important because it weathers relatively easily, releasing essential elements like iron and magnesium that contribute to soil fertility. Tremolite, Actinolite, and Diopside are also minerals, but they belong to different mineral groups (like pyroxenes for Diopside) or are less common/less reactive in soil environments compared to Hornblende. Therefore, Hornblende's abundance and weathering characteristics make it the most significant amphibole in soil science.