Psychology Exam review part 2 Flashcards
- Describe the three parts of the neuron.
- cell body
- dendrites
- Axon
- Describe the three kinds of neurons and compare their functions.
- Sensory – carry messages IN from the body’s sensory receptors to CNS (central nervous system) for processing: afferent direction – from outside CNS to inside CNS. Quantity: 2-3 million
- Motor – carry messages away from the brain and spinal cord and towards muscles that control their flexion and extension. Efferent direction – from inside the CNS to outside CNS. Quantity: 2-3 million
- Interneurons – (in the brain and spinal cord) process information between the sensory input and motor output. Within CNS: neuron to neuron. Quantity: 10-100 billion
To reverse effects of neurotoxic venom from a snakebite, which of the following actions would likely be most effective?
give the patient a substance that would allow the body to resume transmission of acetylcholine.
explain what happens to neurotransmitters after transmission.
3 possibilities
- decomposed by specific enzyme - reuptake – the process whereby neurotransmitter molecules that have been released into the synapse are reabsorbed into the axon terminals of the presynaptic neuron - continues binding
what are the main neurotransmitters
glutamate
GABA
Dopamine
Serotonin
epinephrine and norepinephrine
endorphin
Describe the functions of the neurotransmitters.
Glutamate – most common excitatory neurotransmitter. Used in formation of new memories. Implicated in triggering epileptic seizures.
GABA (Gamma-amino butyric acid) – the primary inhibitory neurotransmitter. Lowers arousal, anxiety, excitation. Facilitates sleep.
Acetylcholine (Ach) – involved in muscle action, learning and memory. Deterioration of Ach neurons implicated in Alzheimer’s disease.
Dopamine – influences movement, learning, attention and emotion. Oversupply linked to schizophrenia. Undersupply linked to Parkinson disease.
Serotonin – influences mood, hunger, sleep and arousal. Undersupply linked to depression.
Epinephrine and norepinephrine – both are catecholamine chemicals with very similar structures. Complimentary pair play major role in sympathetic NS reactions (responding to emergencies, alertness, arousal and mood). Sam chemical used in endocrine system (adrenaline and noradrenaline)
Endorphin – natures pain killer / “natural” morphine. Also involved in emotions in limbic system – E.g. anxiety, fear, tension, pleasure and pain.
Explain the neurology of addiction
brain maintains homeostasis – increases or decreases neurotransmitters to compensate effect of addictive substance. Need increased dosage to experience same effect – unoccupied sites create craving / dependence. Brain “learns” to anticipate consumption – makes “pre-emptive” adjustment – overdose potential.
agonists
drugs that enhance or mimic the effects of a neurotransmitters action.
- direct agonists are drugs that can bind to receptor sites
- indirect agonists facilitate neurotransmitters by increasing the release and availability of neurotransmitters
antagonists
inhibit neurotransmitter activity by blocking receptors or preventing synthesis of the neurotransmitter.
nicotine
an Acetylcholine agonist – it stimulates the receptor sites for this neurotransmitter.
Xanax
a GABA agonist, meaning it causes relaxation by increasing the activity of this inhibitory neurotransmitter
cocaine and meth
stimulants that increase release of dopamine and norepinephrine and/or block reuptake of dopamine. Perceived as pleasurable and associated behaviors are reinforced
opiates
agonists that mimic endorphins by attaching to their binding sites
alcohol
generally depress neural activity throughout brain
Explain how an addict might overdose on the usual dosage.
Brain “learns” to anticipate consumption – makes “pre-emptive” adjustment – overdose potential.
Describe the sympathetic and parasympathetic nervous systems.
Sympathetic – prepares the body to react and expand energy in times of stress (active during fight or flight response) blood is directed to muscles. Heart rate and perspiration increase. Digestive processes slow. – responses that prepare the body for action
Parasympathetic – maintains body functions; conserves resources (active during rest and digestion) following sympathetic arousal, it works to return the body to a baseline, nonemergency state.
neuron
major type of cells that are responsible for sending and receiving messages throughout the body
soma (cell body)
he part of neuron that contains the nucleus that houses the cell’s genetic material.
axon
transports information in the form of electrochemical reactions from the cell body to the end of the neuron
neurotransmitter
chemicals that function as messengers allowing neurons to communicate with each other.
dendrites
small branches radiating from the cell body that receive messages from other cells and transmit those messages toward the rest of the cell.
glial cells
are specialized cells of the nervous system that are involved in mounting immune responses in the brain, removing waste, and synchronizing the activity of the billions of neurons that constitute the nervous system.
myelin sheath
a fatty sheath that insulates axons from one another, resulting in increased speed and efficiency of neural communication.
multiple sclerosis
a disease in which the immune system does not recognize myelin and attacks it.
resting potential
relatively stable sate during which the cell is not transmitting messages
action potential
a wave of electrical activity that originates at the base of the axon and rapidly travels down its length
refractory period
the brief period in which neurons can not fire
presynaptic cell
cell that releases chemicals (before the synapse)
postsynaptic
cell that receives this input (after the synapse)
all or none principle
individual nerve cells fire at the same strength every time and action potential occurs
synaptic cleft
the minute space between axon terminal and the dendrite
reuptake
a process whereby neurotransmitter molecules that have been released into synapse are reabsorbed into the axon terminals of the presynaptic neuron.
hypothalamus
a brain structure that regulates basic biological needs and motivational systems
Pituitary gland
the master gland of the endocrine system that produces hormones and sends commands about hormones production to other glands of the endocrine system.
Adrenal glands
a pair of endocrine glands located adjacent to the kidneys that release stress hormones, such as cortisol and epinephrine.
genes
the basic units of heredity; genes are responsible for guiding the process of creating the proteins that make up our physical structures and regulate development and physiological process throughout the lifespan
genotype
the genetic makeup of an organism – the unique set of genes that comprise that individuals genetic code.
phenotype
the physical traits or behavioral characteristics that show genetic variation, such as eye color, the shape and size of facial features, and even personality.
behavioral genomics
the study of DNA and the ways in which specific genes are related to behavior