Hydrogen bonds is holding together the two strands of nucleic
<span>Covalent bonds hold the atoms and molecules together in each of the amino acid chains. Two complimentary chains are held together by hydrogen bonds to form a double-helix.</span>
Calcium in the teeth provides appropriate pH levels in the mouth.
The ability of an organism to survive and reproduce in its environment is called adaptation. Fitness is a result of adaptation.
An ultrasound uses sound waves to produce images of a baby.
Hello.
There are a couple things needed for natural selection.
Natural selection is organisms become comfortable and changer where they are newly located. Where they can live and get more off springs.
First, You will need <u>heredity</u> which passes traits to an offspring.
Second, <u>reproduction</u> that is needed to to copy traits and give them to the offspring.