Human olfactory system. Computer artwork showing the olfactory
bulb (top) full of olfactory neurons (nerve cells), and an olfactory
receptor cell (yellow, vertical). The olfactory bulb is situated in the
forebrain (prosencephalon). It has many olfactory receptor cells that
project into the epithelial lining (pink) of the nasal cavity. The
receptors (bottom, long, thin) embedded in the membrane of the receptor
cells pick up smell information from molecules inhaled through the nose.
This information is transmitted to the olfactory bulb and sent as a
nerve impulse to the brain.
Neck pain. Conceptual computer artwork showing pain (represented
as the red area) in the neck. The skull (top), upper spine, ribs and
collarbones are shown within an outline (blue) of this part of the body.
Lactobacillus sp. bacteria, colored scanning electron micrograph
(SEM). Lactobacillus bacteria are probiotic bacteria, which are useful
for human and animal health as they produce bacteriocins (toxins that
kill off competitive bacteria), which prevents infection by pathogenic
bacterial strains. They are usually added to probacterial foods such as
yogurts and health bars. Magnification: x12,350 when printed 10
Pain messages are transmitted through a
peptide transmitter known as Substance P (yellow spheres) to spinal
neurone cells in the spinal cord. At center left a spinal neurone has
been opened to show the relation between the Substance P and its
receptor sites (yellow c-shaped). At bottom right a spinal interneurone
is just visible with a short axon terminating on an axon of the spinal
neurone. Here receptor sites (red c-shaped) of opiopeptins (red spheres)
are found. Opiopeptins are contained in analgesic drugs and may
alleviate pain because they inhibit the release of the Substance P.