Virus: an infective agent that typically consists of a nucleic acid molecule in a protein coat, is too small to be seen by light microscopy, and is able to multiply only within the living cells of a host.
Bacteria: a member of a large group of unicellular microorganisms which have cell walls but lack organelles and an organized nucleus, including some which can cause disease.
Fungi/fungus: any of a group of spore-producing organisms feeding on organic matter, including molds, yeast, mushrooms, and toadstools.
Protozoa: a phylum or group of phyla that comprises the single-celled microscopic animals, which include amoebas, flagellates, ciliates, sporozoans, and many other forms. They are now usually treated as a number of phyla belonging to the kingdom Protista.
Homointernal adalah hewan yang bersuhu tubuh panas dan tetap hewan-hewan ini adalah:
1)Ikan, terbagi
-ikan hiu
-ikan pari
2)Amfibi terbagi
-Kodok
3)Reptil
-buaya
-kura-kura
4)Burung terbagi
-ayam
-merak
-kasuari
there are 88 constellations in total
Answer;
Cycilc AMP
Explanation;
-Second messengers are molecules that relay signals received at receptors on the cell surface; such as the arrival of protein hormones, growth factors, etc., to target molecules in the cytosol and/or nucleus.
-Many of the chemical messengers such as hormones, that transmit messages from one cell to another never enter the target cell, these molecules are known as first messengers which work by binding to a specific receptor on the cell surface. The receptor then stimulates or inhibits the production of a so-called second messenger within the cell.
-The second messenger are small molecules such as Cyclic AMP, which activate an effector within a cell.