Tercer Parcial Flashcards
The nervous system divides into…
Central and peripheral
Components of the central nervous system:
Brain and spinal cord
Components of the peripheral nervous system:
Nerves
Functions of the nervous system:
Regulate operations of the body, muscles and glands by sending impulses or signals
They are also called nerve cells and are excitable cells that make up the nervous system
Neurons
Name the three types of neurons
Sensory, inter and motor
Type of neurons activated by stimuli (light, touch)
Sensory neurons
Type of neurons that receive and send signals from and to neurons
Inter neurons
Type of neurons that control muscles and glands
Motor neurons
What are the three parts that all neurons have?
Cell body, dendrites and axon
Part of the neuron that contains the nucleus and organelles
Cell body
Part of the neuron that consists of branched cytoplasmic extensions that can pick up messages from other nerve cells
Dendrites
Part of the neuron that consists of a cytoplasmic extension that transmits electrical signals and releases chemical signals at its endings
Axon
Type of neuron that holds other neurons in place and produces myelin
Neuroglia or glial cells
Increases the speed at which signals travel along an axon
Myelin
Brief transversal of the electric gradient across the plasma membrane
Action potential
They carry messages between cells
Chemical signals
Region where a neuron’s axon terminal transmits signals to another cell
Chemical synapse
Name the 6 neurotransmitters
Acetylcholine, epinephrine, norepinephrine, dopamine, serotonin and endorphins
Neurotransmitter that induces skeletal muscle contraction, slows cardiac rate and affects memory
Acetylcholine
Neurotransmitters that speed heart rate, dilate pupils and airways and increase anxiety
Epinephrine and norepinephrine
Neurotransmitter that has roles in memory, learning and motor control
Dopamine
Neurotransmitter that elevates mood
Serotonin
Neurotransmitters that elevate mood, promote feelings of well being and decrease pain
Endorphins
What are the two divisions of the peripheral nervous system?
Somatic and autonomic
Division of peripheral nervous system that controls the skeletal muscles and voluntary moves
Somatic nervous system
Peripheral nervous system division that relays signals to smooth and cardiac muscle and glands. It controls involuntary moves
Autonomic nervous system
Which are the two divisions of the autonomic nervous system?
Parasympathetic and sympathetic
Division of the autonomic nervous system that activates when relaxed, release acetylcholine
Parasympathetic division
Division of the autonomic nervous system that activates when excited or in danger. Releases norepinephrine
Sympathetic division
Membranes that enclose and protect the brain and spinal cord in the central nervous system
Meninges
Protective mechanism that prevents unwanted substances from entering the cerebrospinal fluid
Blood brain barrier
There are two types of tissue in the brain and spinal cord, which are:
White (bundles of axons) and gray (cell bodies, dendrites and neuroglial cells)
Portion of the central nervous system that runs through the vertebral column and connects the peripheral nerves with the brain
Spinal cord
Is an automatic response to stimuli
Reflex
It has an average weight of 3 pounds (1,240 grams) and 100 billion interneurons
Brain
Is divided into right and left hemispheres by a fisure
Brain
Thick band of tissue that connects the two brain hemispheres
Corpus callosum
Outer layer of gray matter in each hemisphere that has functions in language and abstract thought
Cerebral cortex
Name the 4 lobes of the brain
Frontal, parietal, occipital and temporal
Brain lobe that controls motor skills, expressive language and reasoning
Frontal lobe