Question

Which of the following statements about the basic structural features of DNA are true? Select all true statements. Select all true statements. The major and minor grooves prevent DNA binding proteins from making contact with nucleotides. In a DNA macromolecule, the two strands are complementary and antiparallel. The twisting of the DNA double helix is attributed to the tight packing of DNA bases and base-stacking. The major and minor grooves form in the DNA helix because the DNA strands are antiparallel.

Answer 1

The true statements about the basic structural features of DNA include the complementary and antiparallel nature of the two strands, the twisting of the double helix due to base packing, and the formation of major and minor grooves.

Step-by-step explanation:

The true statements about the basic structural features of DNA are:

1. In a DNA macromolecule, the two strands are complementary and antiparallel. This means that one strand of DNA runs in the 3' to 5' direction, while the other strand runs in the 5' to 3' direction.

2. The twisting of the DNA double helix is attributed to the tight packing of DNA bases and base-stacking. The hydrogen bonds between the nitrogenous bases hold the two strands together and contribute to the helical structure of DNA.

3. The major and minor grooves form in the DNA helix because the DNA strands are antiparallel. These grooves are binding sites for DNA binding proteins during processes such as transcription and replication.

Answer 2

Option (2) and (3).

Step-by-step explanation:

DNA is the genetic material of all organisms except some viruses. DNA is composed of the nitrogenous base, pentose sugar and the phosphate group. DNA strands are complimentary to each other.

The DNA strands run in the opposite direction, one strand in 5' to 3' direction and other strand in 3' to 5' direction thus they are anti parallel with each other. The DNA strand can twist with each other which result in the tight packing of DNA base and base stacking. DNA consists of major and minor grooves.

Thus, the correct answer is option (2) and (3).