The sugar-phosphate backbone of DNA is held together by covalent bonds.     The strands of DNA are joined by hydrogen bonds (H-bonds) between the nitrogenous bases o â¦ n either side. Adenine is joined to Thymine by 2 H-bonds. Cytosine is joined to Guanine by 3 H-bonds.
The mother will leave the nest and the newly hatched chicks sometimes for long periods of time to eat, drink or take a bathroom break. In some species the father will then take over nest duties, but in hummingbirds, itâs up to the mother to tend the eggs and the babies.
Hummingbird babies are born blind and naked without feathers. At first, the hummingbird mother will keep her babies warm by sitting on the nest. See a gallery of photos of a hummingbird nest and the first 20 days of the chicks in the nest before they fledge the nest.