I believe the answer is this:
DNA replication is called semi-conservative because half of the original double-helix appears in one daughter strand formed in replication if you need any more help then please comment and let me know ok. :)
On the planet earth. They exist in what we call the "world", which holds all seen life.
Natural selection act directly upon <u>Alleles</u>
Explanation:
Genes, such as that of fur color, have many variants called alleles. Natural selection act on the alleles and chooses the best fit for an environment and eliminates the disadvantageous ones from the population over generations. Mutations are a rare occurrence that increases the number of allelic variants of a genes on which natural selection can act upon.
Different enzymes have specific active sites which can only catalyze one <span>substrate. Enzyme-substrate complexes are produced only when the substrate fits into the active site :)</span>
Brain size has increased nearly 3x in 4 million years.
