Answer: negatively; electron.
In a chemical bond, proton and neutron didn't take action since they are located in the middle(nucleus) of the atom. The electron which on the outer side of an atom can interact with another electron from an other atom/molecule. Electron has negative charge, while proton is positive and neutron is neutral.
Enzymes are specialized proteins that speed up chemical reactions, biological catalyst.
Answer: Palisade
Explanation: The epidermis is a protective layer of cells and contains no chloroplasts. The palisade layer contains the most chloroplasts as it is near the top of the leaf. The chloroplasts contain the pigment chlorophyll. The palisade cells are arranged upright.
No they cant be mechanical because then something would have to generate their rays through the inventing of a machine.