Bub
The molecular mechanisms by which environments can trigger or block genetic expression
Epigenetics
arouses the body, mobilizing energy for stressful situations like accelerating heartbeat
Sympathetic nervous system
branching extensions of a neuron that receive messages and conduct impulses to the cell body
Dendrite
neurons that carry messages from the body’s tissues and sensory organs to the brain and spinal cord
Sensory neurons (afferent)
a layer of fatty tissue that surrounds the axon and helps the speed of neural impulses, as signals hop from node to node
Myelin sheath
The controversy over the relative contributions of biology vs experience on our psychological traits and behaviors
Nature v. Nurture
the brain and the spinal cord
Central Nervous System
A paused state where no action potentials can occur until the neuron returns to its resting potential, then they can fire again
Refractory period
The positively charged ions are pumped back out of the membrane, returning the insides of an axon to a negative state
Repolarization
The domino effect causing the axon’s channels to open and more positive ions to come in
depolarization
simple, automatic response to a sensory stimulus that only involves the spinal cord
Reflexes
Neurons within the brain and spinal cord that communicate internally and process information between the sensory inputs and motor outputs
Interneurons
A neuron will either fire or not fire, there is no in-between
all-or-none response
controls the glands and muscles of internal organs; involuntary
Autonomic nervous system
A disease that causes the immune system attacks the myelin sheath that covers nerve fibers and causes communication problems between your brain and the rest of your body
multiple sclerosis
controls the skeletal muscles; under voluntary control (skeletal nervous system)
Somatic nervous system
a nerve cell, the basic building block of the nervous system
Neuron
neurons that carry outgoing information from the brain and spinal cord to muscles, tissue, organs, and glands
Motor neurons (efferent)
When the axon has a negative charge inside it and a positive charge outside
resting potential
When stress subsides, calms body, conserves energy like decreasing heartbeat
Parasympathetic nervous system
a neural impulse; an electrical charge that travels down the axon
action potential
extension of a neuron which pass messages to other neurons or to muscle or glands
Axon
the sensory and motor neurons that connect to the central nervous system to the rest of the body
Peripheral nervous system
information highway connecting the peripheral nervous system to the brain
spinal cord
the brain and the spinal cord
Central nervous system