Cortex is the stores the food and water for roots
Answer: The reason is because DNA polymerase which is the enzyme that catalyzes the synthesis of DNA has a 3'->5' exonuclease activity that double-checks each nucleotide after it is added.
Explanation: The 3'->5' exonuclease activity of DNA polymerase allows the enzyme to double-check and remove a newly added wrong nucleotide. It is highly specific for mismatched base pairs. When the DNA polymerase adds a wrong nucleotide to the growing strand, translocation of the enzyme to the position where the next nucleotide is to be added is halted, but the exonuclease activity of the DNA polymerase removes the incorrectly paired nucleotide so that replication can continue. The process of double-checking a newly added nucleotide and removal of any incorrectly paired nucleotide by the DNA polymerase is called proofreading.
C. The problem of endangered species
This type of fossil is called a mold. A cast fossil forms when a mold
fossil is filled with some form of mineral, usually through the seepage
of water depositing the minerals within the mold. In time, the mold is
filled and the materials deposited harden, creating a replica of the
original fossil.
Hope this helps you :p
12. Hinny
13. Microscope
14. Recessive
15. Mutations
