Action Potential

  • “The change in voltage that occurs across the membrane of a nerve or muscle cell when a nerve impulse is triggered. It is due to the passage of charged particles across the membrane and is an observable manifestation of the passage of an impulse” (“Action Potential,” 2010).


  • “Reduced sensibility to pain, without loss of consciousness and without the sense of touch necessarily being affected” (“analgesia,” 2010).


  • “A class of drugs that depress the activity of the central nervous system and have sedative and hypnotic effects” (“barbiturate,” 2006).


  • “Relating to, situated at, or forming the base,” (“Basal,” 2016).


  • “A general term often used rather indiscriminately to describe permanent wetland in which communities of plants grow on generally rather acid waterlogged ground,” (“bog,” 2010).


  • The top shell


  • “Pertaining to the tail” (“caudal,” 2014).

Circadian Rhythm

  • “Any 24-hour periodicity in the behavior or physiology of animals or plants. Examples are the sleep/activity cycle in many animals and the growth movements of plants. Circadian rhythms are generally controlled by biological clocks” (“circadian rhythm,” 2010).

Compound eye

  • An eye which is comprised of multiple chamber, each containing its own lens.
    • Compound eyes are found in arthropods and other invertebrates.
    • Vertebrates typically have “simple eyes” which are comprised of only one chamber with one lens.


  • “A measure of the ability of a sample of water to carry an electric current, which reflects its concentration of an ionized substance,” (“Conductivity,” 2007).

Confocal Imaging

  • “A form of light microscopy that allows successively deeper layers of a fixed or living specimen to be viewed with astonishing clarity” (King, 2013). Confocal imaging makes seeing the detail of a 3D image feasible.


  • “One of the two types of light-sensitive cells in the retina of the eye. Cones are essential for acute vision and can also distinguish colors”(“cone,” 2010).


  • “Relating to the crown of the head or of a tooth. The coronal plane divides the body into dorsal and ventral parts” (2010).


  • “A small natural stream, smaller than a river,” (Park, 2013).


  • The nucleus was removed.


  • “The external branch on the protopodite of a typical limb of a crustacean” (“Exopodite,” 2016).


  • “In neurology, any structure containing a collection of nerve cell bodies and often also numbers of synapses” (“ganglion,” 2008).


  • “The chemistry of the tissues, as studied with a combination of the methods of chemistry and histology” (“histochemistry,” 2006).

Hypoxic water

  • “Water which has a dissolved oxygen concentrations of less than 2 parts per million (ppm), which makes it difficult for most aquatic life to survive and reproduce” (Park 2013).


  • “A form of histochemistry in which appropriately labelled antibody preparations are used to detect specific structures in tissues” (“immunohistochemistry,” 2006).


  • “The quantity that measures the opposition of a circuit to the passage of a current and therefore determines the amplitude of the current” (“Impedance,” 2009).


  • “A membrane or layer of tissue covering any organ of the body” (“integument,” 2014).


  • “A relatively short neuron, which in vertebrates is confined to the grey matter of the central nervous system, that provides a link between a sensory neuron and a motor neuron in a polysynaptic reflex” (“interneuron,” 2009).


  • “The colored part of the eye. It controls the amount of light that enters the pupil in the center of the eye by increasing or decreasing the size of the pupil. These changes are brought about by muscles in the iris contracting or relaxing” (“iris”).


  • “Any of several multiple forms of the same protein that differ in their primary structure, but retain the same function” (“isoform,” 2006).
  • “In electrophysiology, the time between onset of a stimulus and peak of the ensuing action potential” (“Latency”, 2010).


  • “The dark brown pigment produced in response to solar radiation by melanocytes in the skin, the retina, and hair. It provides protection from exposure to ultraviolet radiation” (“melanin,” 2007).


  • “A photopigment found in a subpopulation of retinal ganglion cells that are intrinsically photosensitive and are involved in photo-entrainment of behavior” (“melanopsin,” 2006).


  • “Containing normal levels of oxygen, (95% O2, 5% CO2)” (Buck & Bickler 1995; Pamenter et al., 2008).

Numeral Aperture

  • Refers to the amount of light being let into the microscope.


  • “A gene or protein found in different species that are so similar in their nucleotide or amino acid sequences that they are assumed to have originated from a single ancestral gene” (King, 2007).

PCR (Polymerase Chain Reaction)

  • “A technique of molecular genetics in which a particular sequence of DNA can be isolated and amplified sufficiently to enable genetic analysis” (“polymerase chain reaction,” 2010).


  • The synchronization of the body’s circadian rhythm that is initiated or reset by the presence of light.


  • The underbelly of a turtle


  • “Pentobarbitone sodium, a short-acting barbiturate drug and central nervous system depressant, used as a sedative and hypnotic, and sometimes taken as a street drug” (Coleman 2008).


  • The peritoneum is the fluid filled membrane that surrounds the peritoneal cavity or abdominal cavity of the turtle. The peritoneal cavity houses all of the abdominal organs in the turtle.


  • “To render active or reactive by means of light” (“photoactivate,” 2006).


  • “A sensory cell or group of cells that reacts to the presence of light. It usually contains a pigment that undergoes a chemical change when light is absorbed, thus stimulating a nerve,” (“photoreceptor,” 2006).


  • “Toward the back of the body” (Kent, 2006).

Pre-hybridization Buffer

  • The buffer solution without the probes that was applied to the tissues to prevent them from drying out.

Proteinase K

  • An enzyme that was used to break down the membranes of the iris cells, so that the stain, identifying the melanopsin mRNA could be injected into the cells.
  • Protopodite: “the basal part of a typical limb of a crustacean consisting of two more or less consolidated segments and bearing at its distal extremity an exopodite or endopodite or both” (“Protopodite,” 2016)

qPCR (Quantitative Polymerase Chain Reaction)

  • Unlike general PCR, qPCR provides a quantitative measurement of the rate of formation of the product through the comparison of the rates of formations of different products.


  • “The light-sensitive membrane that lines the interior of the eye. The retina consists of two layers. The outer layer, called the pigment epithelium is pigmented, which prevents the back reflection of light and consequent decrease in visual acuity. The inner layer contains nerve cells, blood vessels, and two types of light-sensitive cells (rods and cones)” (Martin, 2008).

Retinal Pigmented Epithelium

  • “The layer of phagocytic epithelial cells containing many pigment granules that are opposed to the photoreceptors of the eye and internalize discs shed from the rod outer segment” (“pigmented retinal epithelium,” 2010). This layer of cells serves a protective an nutritive role. The phagocytic epithelial cells engulf particles that may be harmful to the retinal cells. Furthermore, this layer is black and therefore, can absorb stray UV rays of light. This ability both protects the cell and allows the organism to see better.


  • A saline solution that includes ion concentrations that are specific to the extracellular fluid or blood plasma of the organism. The solution does not contain any red blood cells, and is characteristic for every organism. The ringer preserves the cells of the retina during the dissection. Water cannot be used in place of ringer because it will create a hypotonic solution, causing retinal cells to burst, as a result of the inward flow of water.


  • One of the elongate, unicellular photoreceptors in the vertebrate retina involved with vision in dim light. Rods do not discriminate color differences (“rod,” 2010).


  • “A beaklike projection” (“rostrum,” 2014)


  • “Of, relating to, or situated in the median plane of the body or any plane parallel thereto” (“saggital,” 2016).


  • “One of the hard components into which the external skeleton of an invertebrate may be divided (e.g. an exoskeleton plate of an arthropod (Arthropoda) in which the sclerites are connected to one another by flexible cuticular membranes). Sclerites are made from sclerotin, which is principally chitin and protein, and frequently contains waxes or calcium salts” (“Sclerite,” 2009).

Spike Activities

  • Action potentials or spikes in electric current measured by the electrodes.


  • “The ventral region of a segment of the body of an insect, if the region is composed of sclerotized cuticle. (If not, the region is termed a ‘sternum’.)” (“sternite,” 2014).


  • “A low‐lying area of wetland that is usually at least partially flooded, is covered with grasses and trees, has better drainage than a bog, has more woody plants than a marsh, and does not accumulate deposits of peat. Swamps may be freshwater or saltwater, and tidal or non‐tidal,” (“swamp,” 2010).


  • “In Crustacea, one of the body appendages that are modified to increase their resistance to water, often by the possession of fringed setae, and that are used to propel the animal through the water” (“Swimmeret,” 2009).


“The minute gap across which nerve impulses pass from one neuron to the next, at the end of a nerve fiber” (“synapse,” 2008).


  • “Of or relating to the temple” (Martin, 2015).


  • “In Arthropoda, a thickened plate on the dorsal side of a segment” (“tergum,” 2008).


  • “The degree of cloudiness in water due to the presence of suspended solids,” (Park, 2013).