A single molecule is the one that is responsible for initiating a signal transduction pathway. The answer in this question is a single molecule. Molecule is defined as an electrically neutral group of two atoms or more held together by a chemical bonds.
Your body is responding to the immense heat of the sun and your body emits sweat from your body of the effort to cool your body down so that you don't get too hot
Plantae: Autotrophic, Multi- or Monocellular, have cell walls as well as a membrane, have a chloroplast making the characteristic green color and to capture sunlight for photosynthesis. Break down generated glucose into it's components.
Animalia: Heterotrophic, Multi- or Monocellular, have a cell membrane made of a phospholipid bilayer, and many mitochondria to aid with movement energy. Feed on plants or other animals. Eukaryotic cells.
Fungi: Heterotrophic, most Multicellular, have a rigid cell wall made of chitin, specialized cells to aid with decomposition of dead organic matter. Eukaryotic cells.
Protista: Can be plant-like, animal-like, or fungus-like. Most are single-celled, may be chemosynthetic or photosynthetic. Eukaryotic cells.
Archeabacteria: Prokaryotic. Do not have nuclei or membrane-bound organelles. Move around using a flagellum to propel itself. Lives in mainly fluid environments (air, water). Separated from Eubacteria due to it's high tolerance of extreme conditions, such as high salinity, no oxygen, burning heat, or freezing cold. Can be chemosynthetic or anaerobic, as well as aerobic.
Eubacteria: Normal, everyday bacteria. Prokaryotic, chemosynthetic, anaerobic, or aerobic. Do not have nuclei or membrane-bound organelles. Mobile using a flagellum to propel itself.
