Answer: B
Explanation:
During polymerization of nucleotides to form nucleic acids, the hydroxyl group on the phosphate group attaches to the 3’ carbon of a sugar of one nucleotide to form an ester bond to the phosphate of another nucleotide. The reaction forms a phosphodiester linkage and eliminates a water molecule.
The DNA strands generally runs from 5 prime to 3 prime direction.
Answer:
D. A mutation causing uncontrolled cell division
Explanation:
Cell division is controlled by various mechanisms. Any mutations in the genes regulating the cell division lead to uncontrolled cell division. Loss of control over the process of cell division leads to the formation of tumors.
These tumors may cause cancer if they are transformed into malignant tumors. Hence, a mutation that causes loss of control over cell division is harmful.
Answer:
Option B
Explanation:
ODD means Oppositional Defiant Disorder while CD means Conduct disorder.
Without initial presence of defiant disorder symptoms, Oppositional defiant disorder are not precursor to the development of conduct disorder.
Oppositional Defiant Disorder and Conduct Disorder are much more predominant in boys than in girls.
According to reseaches carried out,to boys, Oppositional Defiant disorder is a precursor to conduct disorder.
Answer:Sclerenchyma
Explanation:Sclerenchyma is thick walled dead lignified cells, they are hard and elastic. The sclerenchyma cells are divided into two groups namely fibers and sclereids. Sclerenchymatous fibers are branched/unbranched, long, hard, pointed cells with tapering ends, thick walls, and narrow lumen.
D. Proteins help control substances by making trans-membrane channels.
