Biological: Neurons, etc Flashcards
nervous system
an extensive network of specialized cells that carries information to and from all parts of the body
neuroscience
a branch of the life sciences that deals with the structure and functions of neurons, nerves, and nervous tissue
biological psychology OR behavioral neuroscience
branch of neuroscience that focuses on the biological bases of psychological processes, behavior, and learning
neuron
the basic cell that makes up the nervous system and that recieves and sends messages within that system
dendrites
branchlike structures that receive messages from other neurons
soma
the cell body of the neuron responsible for maintaining the life of the cell
axon
tubelike structure that carries that neural message to other cells
glial cells
cells that provide support for the neurons to grow on and around, deliver nutrients to neurons, produce myelin to coat axons, clean up waste products and dead neurons, influence information processing, and, during prenatal development, influence the generation of new neurons
myelin
fatty substances produced by certain glial cells that coat the axons of neurons to insulate, protect, and speed up the neural impulse
nerves
bundles of axons coated in myelin that travel together through the body
diffusion
process of molecules moving from areas of high concentration to areas of low concentration
resting potential
the state of the neuron when not firing a neural impulse
action potential
the release of the neural impulse consisting of a reversal of the electrical charge within the axon
all-or-none
referring to the fact that a neuron either fires completely or does not fire at all
synaptic knob
rounded areas on the end of the axon terminals
axon terminals
branches at the end of the axon
synaptic vesicles
saclike structures found inside the synaptic know containing chemicals
neurotransmitter
chemical found in the synaptic vesicles that, when released, has an effect on the next cell
synapse (synaptic gap)
microscopic fluid-filled space between the synaptic knob of one cell and the dendrites or surface of the next cell
receptor sites
three-dimensional proteins on the surface of the dendrites or certain cells of the muscles and glands, which are shaped to fit only certain neurotransmitters
excitatory synapse
synapse at which a neurotransmitter causes the receiving cell to stop firing
antagonists
chemical substances that block or reduce a cell’s response to the action of other chemicals or neurotransmitters
agonists
chemical substances that mimic or enhance the effects of a neurotransmitter on the receptor sites of the next cell, increasing or decreasing the activity of that cell
reuptake
process by which neurotransmitters are taken back into the synaptic vesicles
enzymatic degradation
process by which structure of neurotransmitter is altered so it can no longer act on a receptor
central nervous system (CNS)
part of the nervous system consisting of the brain and spinal cord
spinal cord
a long bundle of neurons that carries messages between the body and the brain and is responsible for the very fast, lifesaving reflexes
afferent (sensory) neuron
a neuron that carries information from the senses to the central nervous system
efferent (motor) neuron
a neuron that carries messages from the central nervous system to the muscles of the body
interneuron
a neuron found in the center of the the spinal cord that receives information from the afferent (sensory) neurons and sends commands to the muscles through the efferent (motor) neurons; interneurons also make up the bulk of the neurons in the brain
reflex arc
the connection of the afferent (sensory) neurons to the interneurons to the efferent (motor) neuron, resulting in a reflex action
neuroplasticity
the ability within the brain to constantly change both the stucture and function of many cells in response to experience or trauma
stem cells
special cells found in all the tissues of the body that are capable of manufacturing other cell types when those cells need to be replaced due to damage or wear and tear
peripheral nervous system (PNS)
all nerves and neurons that are not contained in the brain and spinal cord but that run through the body itself
somatic nervous system
division of the peripheral nervous system consisting of nerves that carry information from the senses to the central nervous system and from the central nervous system to the voluntary muscles of the body
autonomic nervous system (ANS)
division of the peripheral nervous system consisting of nerves that control all of the involuntary muscles, organs, and glands
sensory pathway
nerves coming from the sensory organs to the central nervous system consisting of afferent neurons
motor pathway
nerves coming from the central nervous system to the voluntary muscles, consisting of efferent neurons
sympathetic division (fight-or-flight system)
part of the autonomic nervous system that is responsible for reacting to stressful events and bodily arousal
parasympathetic division
part of the autonomic nervous system that restores the body to normal functioning after arousal and is responsible for the day-to-day functioning of the organs and glands
endocrine glands
glands that secrete chemicals called hormones directly into the bloodstream
hormones
chemicals released into the bloodstream by endocrine glands
pituitary gland
gland located in the brain that secretes human growth hormone and influences all other hormone-secreting glands (also known as the master gland)
pineal gland
endocrine gland located near the base of the cerebrum; secretes melatonin
thyroid gland
endocrine gland found in the neck; regulates metabolism
pancreas
endocrine gland; controls the levels of sugar in the blood
gonads
sex glands; secrete hormones that regulate sexual development and behavior as well as reproduction
ovaries
the female gonads
testes
the male gonads
adrenal glands
endocrine glands located on top of each kidney that secrete over 30 different hormones to deal with stress, regulate salt intake, and provide a secondary source of sex hormones affecting the sexual changes that occur during adolescence
