Control & Coordination Unit Vocabulary

Soma

• An automatic reaction to a stimulus
• The life support of the neuron, containing the nucleus and most organelles
• Bundles of axons that extend from the brain and spinal cord to the rest of the body
• Internally secreting ductless structures that release hormones into surrounding tissue fluid, like blood

Dendrites

• Photoreceptors in the retina that register black and white
• Hormone release caused by altered levels of critical ions or nutrients
• Where the optic nerve exits the eye
• The main receptor of signals on the neuron that extend from the cell body, also known as the input region

Axon

• The medulla oblongata, midbrain, and pons in the brain, responsible for relaying information between the rest of the brain and the spinal cord
• The generator and transmitter of nerve impulses on the neuron that extend from the cell body, also known as the conducting region
• Sensory nerve receptor that is activated by a change in temperature stimulus
• The convex transparent disc that focuses the light that is allowed in and projects it onto the retina in the inner layer

Ganglion

• The life support of the neuron, containing the nucleus and most organelles
• Collection of nerve cell bodies located throughout the human body (not the brain or spinal cord)
• Hormone release caused by neural input
• Small pit in the eye, packed with cones, that gives us our sharpest and clearest vision

Nerve

• When the cell gets even more negative in charge on the inside before returning to its resting state, a refractory period
• Stem cells that make new gustatory epithelial cells
• Bundles of axons that extend from the brain and spinal cord to the rest of the body
• The medulla oblongata, midbrain, and pons in the brain, responsible for relaying information between the rest of the brain and the spinal cord

Axon Terminal

• The end of the axon that releases neurotransmitters at a synapse when a nerve impulse is received, also known as the secretory region
• Photoreceptors in the retina that register black and white
• Taste receptor cells
• When a hormone can't do its job fully without another hormone present

Myelin Sheath

• Covering on long axons (nerve fibers) that protects and electrically insulates them to increase the speed of nerve impulse transmission
• The junction between two neurons that mediates the transfer of a signal from the presynaptic neuron to the postsynaptic neuron or an effector cell
• Opening in the center of the iris that allows light into the eye
• Transmit information from central nervous system to the rest of the body (efferent neurons)

Nodes of Ranvier

• Hormone release caused by altered levels of critical ions or nutrients
• Covering on long axons (nerve fibers) that protects and electrically insulates them to increase the speed of nerve impulse transmission
• The sensory organ of taste, mainly located in the papillae
• Unmyelinated gaps in the myelin sheath that aid in increasing the velocity of nerve signal conduction

Sensory Neurons

• Transmit information from sensory receptors to the central nervous system (afferent neurons)
• A short-lived, localized change in the membrane potential that can vary in strength, usually caused by a movement of a few
• Sensory nerve receptor that is activated by a change in temperature stimulus
• The white part of the eye that serves as an anchoring site for extrinsic eye muscles; part of the eye's fibrous outermost layer

Motor Neurons

• Opening in the center of the iris that allows light into the eye
• ions
• Transmit information from central nervous system to the rest of the body (efferent neurons)
• Covering on long axons (nerve fibers) that protects and electrically insulates them to increase the speed of nerve impulse transmission