Internal and external hydrogen bonds stabilize the DNA molecule. The two strands of DNA stay together by H bonds that occur between complementary nucleotide base pairs. Two hydrogen bonds occur between the adenosine and the thymine base pairs, and between the cytosine and the guanine there are three.he two DNA strands are held together by interchain hydrogen bonds. H-bonds pair the bases in one chain to the complementary bases in the other chain. (A/T and G/C).
What are circadian rhythms? Circadian rhythms are physical, mental and behavioral changes that follow a roughly 24-hour cycle, responding primarily to light and darkness in an organism's environment. They are found in most living things, including animals, plants and many tiny microbes. The study of circadian rhythms is called chronobiology.
It's your own biological clock called your circadian rhythm. Coming from two Latin words: Circa, meaning 'approximately' and dies, meaning 'day,' this 'clock' regulates your sleeping pattern over the course of a 24-hour day. The circadian rhythm is mostly comprised of a group of cells called the suprachiasmatic nucleus (SCN), which is located in the hypothalamus.