enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Composition of the human body - Wikipedia

    en.wikipedia.org/wiki/Composition_of_the_human_body

    Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...

  3. Liquid hydrogen - Wikipedia

    en.wikipedia.org/wiki/Liquid_hydrogen

    Liquid hydrogen also has a much higher specific energy than gasoline, natural gas, or diesel. [12] The density of liquid hydrogen is only 70.85 kg/m 3 (at 20 K), a relative density of just 0.07. Although the specific energy is more than twice that of other fuels, this gives it a remarkably low volumetric energy density, many fold lower.

  4. Cerebrospinal fluid - Wikipedia

    en.wikipedia.org/wiki/Cerebrospinal_fluid

    Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialized ependymal cells in the choroid plexus of the ventricles of the brain, and absorbed in the arachnoid granulations. In humans, there is about 125 mL of CSF at any one time ...

  5. Blood - Wikipedia

    en.wikipedia.org/wiki/Blood

    Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells.

  6. Bicarbonate buffer system - Wikipedia

    en.wikipedia.org/wiki/Bicarbonate_buffer_system

    The tears are unique among body fluids in that they are exposed to the environment. Much like other body fluids, tear fluid is kept in a tight pH range using the bicarbonate buffer system. [15] The pH of tears shift throughout a waking day, rising "about 0.013 pH units/hour" until a prolonged closed-eye period causes the pH to fall again. [15]

  7. Hydrogen - Wikipedia

    en.wikipedia.org/wiki/Hydrogen

    Hydrogen is a chemical element; it has symbol H and atomic number 1. It is the lightest element and, at standard conditions, is a gas of diatomic molecules with the formula H 2, sometimes called dihydrogen, [11] hydrogen gas, molecular hydrogen, or simply hydrogen. It is colorless, odorless, [12] non-toxic, and highly combustible.

  8. Water splitting - Wikipedia

    en.wikipedia.org/wiki/Water_splitting

    Using electricity produced by photovoltaic systems potentially offers the cleanest way to produce hydrogen, other than nuclear, wind, geothermal, and hydroelectric. Again, water is broken down into hydrogen and oxygen by electrolysis, but the electrical energy is obtained by a photoelectrochemical cell (PEC) process.

  9. Cellular respiration - Wikipedia

    en.wikipedia.org/wiki/Cellular_respiration

    The citric acid cycle is also called the Krebs cycle or the tricarboxylic acid cycle. When oxygen is present, acetyl-CoA is produced from the pyruvate molecules created from glycolysis. Once acetyl-CoA is formed, aerobic or anaerobic respiration can occur. When oxygen is present, the mitochondria will undergo aerobic respiration which leads to ...