Answer:
A. Nuclear fusion
Explanation:
The sun generates energy from a process called nuclear fusion. During nuclear fusion, the high pressure and temperature in the sun's core cause nuclei to separate from their electrons. Hydrogen nuclei fuse to form one helium atom.
Answer: A. Nitrogen
Explanation: Nucleic acids contain the same elements as proteins: carbon, hydrogen, oxygen, nitrogen; plus phosphorous (C, H, O, N, and P). Nucleic acids are very large macromolecules composed of repetitive units of the same building blocks, nucleotides, similar to a pearl necklace made of many pearls.
DNA replication
After the process of DNA replication occurs, each daughter cell receives an exact copy of the parent cell's DNA.
DNA replication is a biological process by which a DNA molecule divides to produce two copies of itself during cell division. DNA replication takes place in all living organisms. During DNA replication, an enzyme known as helicase separates the double helix structure of the DNA molecule into two separate strands which serve as templates for making the new strands of DNA.
Chromosomes are made of condensed coils of DNA. Genes are segments on a chromosome that carry the code for a specific trait. Alleles are contrasting forms of a gene. Dominant means that a particular trait will be visible. Recessive means that a trait will be hidden (unless it is paired with another recessive gene). A trait is how the gene is seen. For example, eye color is a trait.