Answer:
D. Bonds between the strands are relatively weak hydrogen bonds, whereas bonds within the strands are relatively strong covalent bonds
Explanation:
According to Watson and Crick hypothesis on the structure of the deoxyribo nucleic acid, the two double helix strands of the DNA are weakly associated with each other by hydrogen bond. Within the strands, the nucleotide bases are held together by covalent bonds.
<em>The weak hydrogen bond ensures that the two strands are easily separated by the relevant enzyme during the process of replication or transcription. The relatively stronger covalent bond ensures that the nucleotide chains are not broken during the separation of the two strands.</em>
The correct option is D.
Answer:
The carbon cycle is nature's way of reusing carbon atoms, which travel from the atmosphere into organisms in the Earth and then back into the atmosphere over and over again. Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms.
Answer:
Well honestly almost every living things contains cells but in this case yes calcium is made up of cells.
Explanation:
Calcium ions are either pumped out of the cell by a specific plasma membrane, Ca2+-ATPase (PMCA), or back into the sarcoplasmic reticulum by SERCA. The PMCA are encoded by at least four genes, PMCA1 and 4 are the most widely expressed and are the two isoforms expressed in vascular smooth muscle cells.
Answer:
The main difference between T cells and B cells is that T cells can only recognize viral antigens outside the infected cells whereas B cells can recognize the surface antigens of bacteria and viruses.
Explanation: