Chapter 5.1 Flashcards
Neurotransmitter
Chemicals that transmit signals across a synapse from one neuron to another target neuron, muscle cell, or gland cell. They play critical roles in communication within the nervous system.
Example: Acetylcholine, dopamine, glutamate
Nitric Oxide (NO)
A gaseous neurotransmitter involved in various physiological processes, including vasodilation and neurotransmission. It diffuses freely across membranes to influence nearby cells.
Example: NO is important in regulating blood flow
Noradrenergic Neuron
A neuron that primarily uses norepinephrine (noradrenaline) as its neurotransmitter. These neurons are involved in regulating arousal, attention, and stress responses.
Example: Noradrenergic neurons play a role in the fight-or-flight response
Norepinephrine (NE)
Also known as noradrenaline, it acts as both a hormone and neurotransmitter. It is crucial for the fight-or-flight response, increasing heart rate and blood flow to muscles.
Example: NE is released in response to stress
Obsessive-Compulsive Disorder (OCD)
A mental disorder characterized by unwanted repetitive thoughts (obsessions) and behaviors (compulsions) that the individual feels driven to perform. It often leads to significant distress and impairment.
Example: OCD can interfere with daily activities
Parkinson Disease
A neurodegenerative disorder that affects movement control, characterized by tremors, rigidity, and bradykinesia (slowness of movement). It results from the loss of dopamine-producing neurons in the substantia nigra.
Example: Parkinson’s disease is treated with dopaminergic medications
Peptide Hormone
Hormones made of amino acids that regulate various physiological functions. Examples include insulin, which controls blood glucose levels, and oxytocin, which influences social bonding and reproductive behaviors.
Example: Insulin is a peptide hormone
Postsynaptic Membrane
The membrane on the receiving side of a synapse, which contains receptors for neurotransmitters. This membrane undergoes changes in electrical potential in response to neurotransmitter binding.
Example: Postsynaptic membrane activation leads to signal transmission
Presynaptic Membrane
The membrane on the transmitting side of a synapse, where neurotransmitters are released. It contains the machinery necessary for neurotransmitter exocytosis.
Example: Presynaptic membrane contains synaptic vesicles
Quantum (pl. Quanta)
The minimum amount of neurotransmitter released from a presynaptic vesicle into the synaptic cleft. Each quantum produces a small postsynaptic potential.
Example: Quanta release is stochastic
Rate-Limiting Factor
The slowest step in a metabolic pathway that determines the overall rate of the process. In neurotransmitter synthesis, it often involves an enzyme that regulates the production of the neurotransmitter.
Example: Tyrosine hydroxylase is a rate-limiting enzyme in dopamine synthesis
Reuptake
The process by which neurotransmitters are reabsorbed by the presynaptic neuron after being released into the synaptic cleft. This mechanism helps terminate the neurotransmitter’s action and recycle it for future use.
Example: Selective serotonin reuptake inhibitors (SSRIs) block serotonin reuptake
Schizophrenia
A severe mental disorder characterized by distorted thinking, perception, emotions, language, sense of self, and behavior. Symptoms often include hallucinations, delusions, and disorganized thinking.
Example: Schizophrenia has genetic and environmental risk factors
Second Messenger
Intracellular signaling molecules released by the cell in response to exposure to extracellular signaling molecules. They amplify the signal and trigger various cellular responses.
Example: cAMP is a second messenger in the cAMP signaling pathway
Serotonin (5-HT)
A neurotransmitter that regulates mood, appetite, sleep, memory, and learning. Imbalances in serotonin levels are associated with mood disorders such as depression and anxiety.
Example: Selective serotonin reuptake inhibitors (SSRIs) target serotonin reuptake
