Answer:
Option (d).
Explanation:
DNA is the genetic material of all the organism except some viruses. DNA is composed of nitrogenous base, deoxyribose pentose sugar and the phosphate group.
DNA replicatese by semi-conservative mode of replication in which one the daughter DNA consists of one newly synthesized strand and one parental strand. This mode of replication was explained by Messelson and Sthal experiment. The cells from 15N medium are transferred to 14N medium the band of intermediate density was observed. The daughter DNA consists of one 15N DNA strand and one 14N DNA strnd. This strand undergo replication in the 14N medium. This time one low density DNA band ( contains 14N - 14N DNA strand) and one intermediate density band ( 14N-15N DNA).
Thus, the correct answer is option (d).
Answer:
The correct option is H) these acids change the environment.
Explanation:
Soil can be described as the part of the environment where plants grow. In primary succession, life stars arising in an area which has no soil and only rocks, This is possible because lichens are the organisms which can grow on the rocks. Lichens secrete certain acids which break down these rocks and hence soil begins to form when these rocks break. This makes it possible for other plant species to grow on these lands.
Answer:
Ponds:
Shallow & warm
A lot of plant and animal life
Many nutrients
Lakes:
Large, deep, cold
Little sunlight near bottom
Plants mainly along the shore
Ergocalciferol is the form of vitamin d found in plants.