Nervous System
How many nerve cells does the Brian have
100 billion
Myelin begins forming during the -----of the prenatal development how does this explain the sometimes humorous's way a baby's whole body jumps when it's startled
14th week and some of the axons are not completely mylienated
If a neurons cell body were the size of a tennis ball, the axons would be -----and ------. The dendrites would------
A mile long, half an inch thick, and fill a large bedroom
Responsible for much of the stimulation of muscles including the muscles of the gastrointestinal system. Found in sensory neurons and in the autonomic nervous system, has a part in scheduling REM sleep. Stimulation of muscles including digestion schedules REM sleep related to memory of Alzheimer's patients show up to 90% loss of acetylcholine
Acetylcholine
Which of the following neuron transmitters is usually excitatory
Acetylcholine
Found between neurons and blood vessels they serve to structural support regulate nutrients concentration join parts by their abundant cellular process and also form scar tissue after an injury *alcohol kills astrocytes and marijuana
Astrocytes
Which of the following cells in not part of the CNS
Astrocytes
Which of the following cells is found only in the PNS
Astrocytes
Which of the following is a type of neuroglial cell
Astrocytes
When peripheral nerves are damaged
Axons can regenerate
The organs of the CNS are the
Brain and spinal cord
What is glioma
Brain tumors consisting of rapidly dividing neuroglia grows rapidly, excess neuroglia cells very difficult to treat
What are the components of the nervous system
Brain, spinal cords, nerve
Dendrites
Branch nerve cell process that serves as a receptor surface of neurons *receives impulses
Nerves
Bundles of axons/ nerve fibers transmit impulses sensations to the brain
What are the three common features of neurons?
Cell body, dendrites, and axon
What are the two major subdivisions of the nervous system
Central and peripheral
Somatic system
Conscious control
Central nervous system
Consists of the brain and the spinal cord
Peripheral nervous system
Consists of the nerves and connects the (afferent and efferent) (sensory and motor)
What are the functions of the nervous system
Controls reactions to the environment, maintain homeostasis, control voluntary and involuntary muscles
The cytoplasmic extensions that, together with the cell body provide the main receptive surfaces for neurons are
Dendrites
What does phagocytize mean
Destroy
The nervous system
Detects changes in the internal or external environment, controls the movements of muscles and secretion of glands, integrates the info form several sources and uses it to make appropriate responses
When CNS axons are damaged
Do not regenerate
It is an inhibitory reward and fell good chemical opioids affect these levels drugs like cocaine, opium, and alcohol increases the levels of dopamine
Dopamine
Which of the following lists the parts of a reflex arc in the correct sequence
Effector, sensory neuron, receptor, inter neuron, motor neuron
Involved In reduction and pleasure involved in the hibernation process because it's slows general metabolism
Enodrphin
Nodes of ranvier occur between adjacent neurons
False
Neurons can't exist without theses cells. Function to
Filling empty spaces, provide framework, produce myelin, and carry out phagocytosis
The supportive tissue of the nervous system are
Glial cells
In the brain and spinal cord axons with myelin make up the tissue commonly called and the axons without myelin make up the tissue commonly called
Gray matter
Signals from the sensory impulses are brought together 1) create sensation2)add to memory 3) produce thought that will translate sensations into perceptions this allows us to then be able to make either conscious or subconscious decisions
Integrative
Found entirely within the brain and spinal cord functions to transmit impulses from one part of the brain to another part
Interneurons
What does myelin sheath do
It insulates the axon
What does mercury poisoning do
Kills the neurons as they die the neurological cell over grows and creates scar tissue or tumors. Lethal
Scattered throughout the the central nervous system they serve to support neurons and phagocytize and debri
Microglial cells
Carey impulses from the brain/spinal cord to the effectors the most common effectors are muscles and glands
Motor
Carries impulses from the CNS to the various effectors these would include muscles and glands.
Motor
The nervous system function that makes conscious decisions possible is the
Motor function
Axons that are covered with myelin are called
Myelinated
Axons
Nerve fiber that conducts impulses away
The process of transmitting a nerve impulse from one neuron to another involves a
Nerve impulse stimulating presynaptic dendrites to release a neurotransmitter into a synaptic cleft
Neurons are ---- whereas neuroglial cells are----
Nerves, nerve cells
Neurological
Nervous tissue that provide physical support, insulation and nutrients for neurons*gather process, send
Are chemical which allow the transmission of signals from One neuron to the next to synapses
Neuron transmitter
What are the two major types of cells that form nervous tissue
Neurons and astrocytes
What are narrow gaps between the Schwann cells called
Nodes of ranvier
Bringing our nervous system to "high alert" it is prevalent in the sympathetic nervous system, and it increases heart rate and our blood pressure. Our adrenal glands release it into our blood streams, along with its close relative epinephrine. Important for forming memories. Stress tends to deplete our stroke of adrenalin it's excercises restores it amphetamines cause excess the release of it
Norepinephrine
What happens to neurons in the absence of oxygen
Nuclei, changes shape and begins to disintegrate
Cell body
Nucleus containing central part of a neuron
What produces myelin in the brain and spinal cord
Oligodendrites
Found along nerve fibers they serve to produce myelin
Oligodendrocytes
What is the difference between a dendrite and an axon
One receives one sends
The divisions of the nervous system that connects body parts with the central nervous system is
Peripheral nervous system
After spinal cord injury overgrowth of neuroglial cells create ---- which slows the recovery
Scar
What is trigger zone
Sensitive region of the axon
Carry impulses from the peripheral body parts to the brain/spinal cord
Sensory
Uses sensory receptors to gather information such as light, sound, environmental, stimuli, internal body conditions, temperature and converts into nerve impulses which are then sent to the central nervous system
Sensory
Motion and mood to little depression anger control, OCD, increases appetite insomnia IBS fibromyalgia migraines to much affected by hallucinogens(LSD, ecstasy, Prozac, warm milk comforts you
Serotonin
What are axons covered In
Sheath off fatty layers which provide insulation kind of like a bandage wrapped around a finger
Nerve impulse
Signal transmitted by nerve fibers
Which of the following in under voluntary control of the nervous system
Skeletal muscles
All the neurons have a special area where a nerve impulse begins called the
Soma
Clusters of neuron cell bodies are called
Soma
Skeletal muscles contraction is under the control of the
Somatic nervous system
Neuron
Specialized cell transmitting nerve impulses
Myelination is completed sometimes furring -----what potential impact could mal-nutrition have on the nervous system
The time a child starts walking
Nerve impulses are usually transmitted from a dendrite to an axon or nerve cell body
True
How many times will your nerves of your body stretch around the world
Two and a half times
Autonomic system
Unconscious control
Axons without myelin covering are called
Unmylienated
Masses of mylienated nerve fibers appear
White