Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
80 Cards in this Set
- Front
- Back
|
What is the spinal cord?
|
Bridge b/t the brain and body
|
|
|
What are the spinal nerves? |
- Part of PNS. - 31 pairs, each connected to the spinal cord and pertain to a specific body area. - Protected by the hard spinal column. - Made out of sensory and motor fibers. |
|
|
How are spinal reflexes enabled?
|
By spinal nerves.
|
|
|
What is the central nervous system (CNS)?
|
- Brain and spinal cord. - Transmits msgs b/t brain and body - Processes incoming info from PNS - Sends out msgs to muscles, glands, organs |
|
|
What is the peripheral nervous system (PNS)?
|
- Outside of brain and spinal cord. - Made of long axons and dendrites. - Reaches extremities of body. - Handles input and output from CNS for news inside/outside the body. |
|
|
What is the autonomic nervous system?
|
- Involuntary responses - Goes to the glands, blood vessels and organs - Digestion, elimination, heart rate, salivation, perspiration, breathing, sexual arousal |
|
|
What is the somatic nervous system? |
- Voluntary responses - Moving your arms, speaking, working out, etc. - Goes to skin, joints, muscles |
|
|
What is somatic division?
|
- Voluntary movement of skeletal muscles |
|
|
What is autonomic division?
|
- Involuntary. - Self-regulated action of smooth muscles like cardiac muscle. - Controls internal organs and glands. |
|
|
What are the two parts to the Autonomic Nervous System? |
- Sympathetic Nervous System (Fight-or-flight) - Parasympathetic Nervous System (calms, rest and digest) |
|
|
What are nerves?
|
- Bundles of axons - Like cables - part of PNS - 3 types of nerves: afferent, efferent, mixed nerve |
|
|
What is a neuron?
|
- A single cell within the nervous system. - A group of neurons form a nerve cell. - Conduct electrochemical signals - Basic unit of the nervous system |
|
|
What are the three types of neurons?
|
Sensory, motor, and interneurons.
|
|
|
What are glia cells?
|
- Support, nurture, and insulate neurons - Remove debris when neurons die - Maintain neural connections - Modify neural functioning - 10-50x more glial cells than neurons |
|
|
What are the four main functions of glial cells?
|
1. Surround neurons and hold them in place 2. Supply nutrients and oxygen to neurons 3. Insulate one neuron from another 4. Destroy and remove dead neurons (clean up) |
|
|
What are the components of the neuron?
|
The cell body, the dendrite, the axon, the myelin sheath, the glial cells, and the synapse.
|
|
|
What is the cell body and what does it do?
|
Coordinates info-processing tasks and keeps cell alive.
|
|
|
What is the dendrite?
|
Recieves info from other neurons and relays it to the cell body.
|
|
|
What is the axon?
|
Transmits info to other neurons, muscles, or glands.
|
|
|
What is the myelin sheath?
|
Provides insulating layer of fatty material.
|
|
|
What are the glial cells?
|
The support cells in the nervous system.
|
|
|
What is the synapse?
|
The junction b/t one neuron's axon and another cell's dendrites/cell body.
|
|
|
How do neural networks work?
|
The complex webs of interconnected neurons form with experience.
|
|
|
What are the 3 major types of neurons?
|
Sensory neurons, interneurons, and motor neurons.
|
|
|
What are sensory neurons?
|
- Sense/receive info from sensory receptors. - Receive msgs from outside the nervous system (e.g. body tissues, sensory receptors) - Carry msgs to central nervous system through the cranial/spinal nerves. |
|
|
What are interneurons?
|
- Process sensory input/motor output - In brain and spinal cord - Receives info from neurons in same region |
|
|
What are motor neurons?
|
- Carry instructions OUT from CNS to voluntary muscles that move the body
|
|
|
What are neurons?
|
- Electrically excitable cells that process/transmit info through electrical and chemical signals.
|
|
|
What are the different types of neurons specializing in each location? |
Purkinje cell, Pyramidal cell, and Bipolar cell.
|
|
|
What is a neuron made of?
|
- Neurons have a cell body, an axon, and at least one dendrite. - Size/shape vary. |
|
|
What is the Purkinje cell?
|
It has an elaborate treelike assemblage of dendrites.
|
|
|
What are the pyramidal cells?
|
They have a triangular cell body and a single, long dendrite with many smaller dendrites.
|
|
|
What are bipolar cells?
|
They have only one dendrite and a single axon.
|
|
|
What are afferent neurons?
|
- Sensory neurons - Carry impulses from sensory organs (5 senses) TOWARDS the CNS. - Communicates with interneurons. |
|
|
What are efferent neurons?
|
- Motor neurons (and some sensory neurons which adjust sensory sensitivity) - Carry nerve impulses AWAY from CNS to muscles/glands. - In grey matter of spinal cord and medulla |
|
|
How does a reflex action work?
|
The skin receptors carry the sensory neurons from the muscles into the spine, into the spine, to the brain, where the spine's interneurons send motor neurons back from the CNS to the muscles to make movement.
|
|
|
What is the neuron structure?
|
Cell body (soma) - nucleus w/ chromosomes Dendrites - receive info from other neurons Axon - transmits info to other neurons, muscles, glands Myelin sheath - helps efficient transmission of signals to other cells, gaps are nodes of Ranvier, insulating layer of fatty material |
|
|
Where do the neurons communicate?
|
In the synapse, the junction where neurons interact with one another. Small knobs at the end of the axon called terminal buttons secrete neurotransmitters. |
|
|
What are the steps in communication between neurons?
|
1. Junction b/t one neuron's axon and another's dendrites/cell body 2. Neurotransmitters cross the synapse 3. Plays a fundamental role in the communication b/t neurons |
|
|
What is the synapse?
|
The junction b/t the one neuron's dendrites and another's axon/cell body. Neurons do not actually touch one another, there is a small synaptic space b/t them across which info is transmitted. |
|
|
What is the action potential?
|
An electrical impulse that travels down an axon like a wave and chemical changes occur. Ions carry either a +/- High concentration of K+ and negative proteins (A-) inside neuron, as relative to outside, where there is a high concentration of Na+ and Cl-. In resting state, K+ flows inside and outside the neuron freely b/c channels are open Na+ channels are generally closed, making the voltage inside the neurons at REST -70 mV. |
|
|
What is resting potential?
|
"potential energy" b/c it creates an environment for potential electrical impulse (aka action potential). |
|
|
When does action potential occur?
|
When there is a change in the membrane channels. When a threshold is reached (-55 mV). The K+ channels close and Na+ channels open and this increases the + charge inside the neuron relative to the outside (trapped K+ and Na+ inside). This pushes the potential to a maximum value of +40 mV. If it does not, all-or-none law. Action potential occurs at same magnitude regardless if stimulus is at or above this threshold. |
|
|
What is the refractory period?
|
K+ channels open, K+ flows out, Na+ and K+ are thus abundant outside the axon. Imbalance => no action potential. A pump moves the Na+ out of axon (operating only during this period) and moves K+ inside the axon that restores balance inside/outside the axon. |
|
|
When does the refractory period end?
|
- After the action potential reaches +40 mV, membrane channels return to original state. - The neuron can now generate another action potential. |
|
|
Explain the anatomy of the synapse.
|
The presynaptic neuron's axons end in terminal buttons => contain synaptic vesicles => contain neurotransmitters (chemicals that transmit info across synaptic gap). Post synaptic neuron's dendrites ccontain receptor sites, which fit certain neurotransmitters, which bind to specific receptor sites in a lock-and-key system. |
|
|
What happens when the neurotransmitters meet the neurons?
|
After the neurotransmitters stimulate on the receiving neuron's receptors, the chemicals are taken back up into the sending neuron to be used again. |
|
|
What is a neurotransmitter?
|
A chemical substance that is released by a transmitting neuron at the synapse and that alters the activity of a receiving neuron.
|
|
|
What are the major neurotransmitters?
|
Serotonin Dopamine Acetylcholine Norepinephrine GABA Glutamate |
|
|
What is Acetylcholine?
|
Enables muscle action, learning and memory With Alzheimer's, Ach producing neurons deteriorate |
|
|
What is dopamine?
|
Influences movement, learning, attention and emotion High levels linked to schizophrenia, low levels linked to Parkinson's Disease |
|
|
What is serotonin?
|
Affects mood, hunger, sleep arousal Low levels linked to depression |
|
|
What is norepinephrine?
|
Helps control alertness and arousal. Low levels depress mood. |
|
|
What are endorphins?
|
Boots mood, lessens pain. Artificial opiates cause brain to stop producing endorphins. |
|
|
What are serotonin pathways?
|
Networks of neurons that communicate with serotonin help regulate mood.
|
|
|
What are dopamine pathways?
|
Networks of neurons that communicate with dopamine are involved in focusing attention and controlling movement.
|
|
|
When does the cell send the action potential?
|
The neuron receives signals from other neurons; some are telling it to fire and some are telling it not to fire. When the threshold is reached, the action potential starts moving. Like a gun, it either fires or it doesn't; more stimulation does nothing. This is known as the "all-or-none" response. |
|
|
How do neurons communicate (with each other)? |
The action potential travels down the axon from the cell body to the terminal branches. The signal is transmitted to another cell. However, the msg must find a way to cross a gap (synapse) b/t cells. The threshold is reached when excitatory signals outweigh the inhibitory signals by a certain amount. |
|
|
How do neurons link with the brain?
|
The brain is 3 pounds and about 86 million neurons are in the brain.
|
|
|
What are the 3 basic areas of the brain?
|
Forebrain Midbrain Hindbrain |
|
|
Hindbrain?
|
Coordinates info coming into/out of spinal cord. Medulla, Reticular formation, Cerebellum, Pons |
|
|
Midbrain?
|
Tectum, Tegmentum, Neurotransmitters
|
|
|
Forebrain?
|
Divided into 2 areas: cerebral cortex and subcortical areas. Subcortial areas: thalamus, hypothalamus, pituitary gland, amygdala, hippocampus |
|
|
Thalamus
|
Relays/filters sensory info (not smell) and sends to celebral cortex |
|
|
Hypothalamus
|
Regulates body temperature, hunger, thirst, sexual behavior Sends hormonal signals to the pituitary gland which sends these signals to other glands to control stress, digestive activities, and reproductive processes. |
|
|
Pituitary Gland
|
releases hormones that direct the functions of other glands in the body |
|
|
Limbic System
|
hypothalamus, hippocampus, amygdala motivation, emotion, learning, memory |
|
|
Hippocampus
|
creating new memories if damaged, can't remember recent memories |
|
|
Alzheimer's disease
|
neurons stop functioning, lose connnections w/ other neurons, and die affects repair of neurons, disrupts communication within networks & beyond |
|
|
Amygdala
|
formation of emotional memories encodes neutral stimuli (dog) events as fearful if you were attacked by a dog. When see a dog feel fear |
|
|
Basal Ganglia
|
set of subcortical structures that directs intentional movements located near thalamus and hypothalamus receives input from cerebral cortex sends output to motor centers in brain stem striatum => posture and movement |
|
|
Cerebral cortex
|
highest lvl of brain perception, emotion, movement, thought gyri: smooth surfaces sulci: fissures separates cortex into two hemispheres |
|
|
Corpus Callosum
|
connects large areas of cerebral cortex on each side of brain supports communication of info across the hemispheres |
|
|
Occipital lobe
|
processes visual info if damaged: partial/complete blindness |
|
|
Parietal lobe
|
2 parts: somatosensory cortex: skin areas on other side of body motor cortex: initiates voluntary movements, sends messages to basal ganglia, cerebellum, spinal cord takes in info, sends out commands |
|
|
Temporal Lobe
|
Hearing, turns sounds into speech |
|
|
Frontal Lobe |
contains motor cortex specialized areas for movement, abstract thinking, planning, memory, judgement coordinate thought processes that help us manipulate info and retrieve memories |
|
|
Mirror neurons
|
in frontal lobe and parietal lobe in birds, monkeys, humans active when an animal performs a behavior, when another animal observes that animal performing the same behavior |
|
|
Brain plasticity |
reorganization of functions in brain to accommodate changing input from the environment
|
|
|
|
|
