Answer:
a. The directionality of the complementary strand is antiparallel. The double-stranded DNA is antiparallel comprising two strands, which run alongside each other, however, point in reverse directions. In a double-stranded molecule of DNA, the 5 prime ends of one strand align with the 3 prime ends of the other strand, and vice versa.
b. The mediation of base pairing is done by non-covalent hydrogen bonds. It is reversible, that is, the strands can separate and can come combined again without any chemical modification.
The specificity of base pairing is illustrated by hydrogen bonds that is, the first strand produces hydrogen bonds only with a particular base in the second strand, and these two bases produce a base-pair.
c. The interaction or association of non-covalent type, that is, hydrophobic interaction and hydrogen bonding. Collectively, they both are strong. In the process, one base associate with the other base on the complementary strand.
d. The phosphate backbone possesses the tendency to associate with water on the outside of the molecule, and this is favorable chemically as both the strands are held together by hydrogen bond and hydrophobic interaction.
The polar molecules of sugar can produce hydrogen bonds with the surrounding molecules of water. The negatively charged phosphate group associate with the positively charged ions. The nonpolar nitrogen bases are found within the molecule and associate favorably through stacking interactions.
Sugar comes from either sugar cane or sugar beet<span> with the climate of a geographical region being the prime influence on which is grown. In both cases, the juice is extracted from the </span>sugar beet<span> or cane and impurities are removed. It is then crystallised into white sugar, which is 99.95% sucrose.</span>
Answer:
Option (3)
Explanation:
Unconformity is defined as the gaps in the sequence of geological rocks. It is a geological contact that marks the boundary between the different types of rocks. In simple words, they are also known as the time of non-deposition. These unconformities have great significance in the field of geology. They are of 4 types, namely-
(1) Angular unconformity- The sedimentary rocks are initially formed and deposited in an area, after that the area is tilted and erosion takes place. Now, the new sediments are deposited forming an angle, which is commonly known as an angular unconformity.
(2) Non-conformity- When the sedimentary rocks are deposited over the igneous or metamorphic rocks, then it is known as the non-conformity.
(3) Para conformity- When the sedimentary rocks are deposited parallel to the ground surface, and absence of erosion activity, then these surface appears to be a normal (simple) bedding plane. This is known as the para conformity.
(4) Disconformity- When the sedimentary rocks are formed and undergoes erosion, then new sedimentary rocks are deposited over this and diminishes the unconformity. This forms a discontinuity.
Thus, the unconformity arises due to both erosion and lack of rock deposition.
Hence, the correct answer is option (3).
