ch 3 Flashcards
(40 cards)
What are the two major types of cells in the nervous system?
Neurons and glial cells.
What is the primary function of neurons?
Neurons are responsible for communication within the nervous system, using electrical and chemical signals to transmit information.
What is the main role of glial cells in the nervous system?
Glial cells provide support, insulation, and protection for neurons, and they assist in maintaining homeostasis in the brain.
What are dendrites, and what do they do?
Dendrites are branches of neurons that receive input from other neurons and sensory receptors.
What is the function of the axon in a neuron?
The axon carries signals away from the cell body toward other neurons or effector cells.
What is the myelin sheath, and why is it important?
The myelin sheath is a fatty layer covering segments of the axon that insulates the neuron and speeds up neural impulses.
What happens at the axon terminal?
The axon terminal releases neurotransmitters that allow the neuron to communicate with other neurons across a synapse.
How do neurons communicate with each other?
Neurons communicate using both electrical impulses (action potentials) and chemical signals (neurotransmitters).
What are synapses?
Synapses are small gaps between neurons where neurotransmitters are released to transmit signals to the next neuron.
What is neuroplasticity?
Neuroplasticity is the brain’s ability to reorganize and form new neural connections in response to experience or injury.
What is the blood-brain barrier (BBB), and which cells are involved in its formation?
The BBB is a protective barrier that prevents harmful substances from entering the brain. Astroglial cells are involved in creating it.
What is an action potential?
An action potential is a sudden, rapid increase in electrical charge that travels down a neuron’s axon when a threshold voltage is reached.
What are astrocytes, and what function do they serve?
Astrocytes are glial cells that help create the blood-brain barrier and regulate blood flow in response to neuronal activity.
What is the sodium-potassium pump, and what role does it play in neurons?
The sodium-potassium pump is a protein that moves sodium ions out of the neuron and potassium ions into it, helping to maintain the resting potential.
How do glial cells contribute to the myelin sheath?
Oligodendroglia in the central nervous system and Schwann cells in the peripheral nervous system form the myelin sheath around axons.
What neurotransmitter is involved in mood regulation and sleep?
Serotonin is involved in mood regulation, sleep, and appetite.
What is the difference between excitatory and inhibitory neurotransmitters?
Excitatory neurotransmitters trigger action potentials in the postsynaptic neuron, while inhibitory neurotransmitters prevent action potentials.
What is the role of dopamine in the brain?
Dopamine is involved in controlling voluntary movement, mood, and reward mechanisms.
What is the function of GABA?
GABA is the main inhibitory neurotransmitter in the brain, helping to reduce neural activity and promote relaxation.
What is neuroplasticity, and why is it important?
Neuroplasticity refers to the brain’s ability to change and adapt by forming new neural pathways, allowing for learning and recovery after injury.
What is multiple sclerosis (MS), and how does it affect neurons?
MS is a disease that involves the degradation of the myelin sheath on neurons, leading to impaired signal transmission and symptoms like muscle weakness.
How do action potentials travel faster along myelinated neurons?
Action potentials jump from one node of Ranvier (gaps in the myelin sheath) to the next, speeding up conduction through saltatory conduction.
What is synaptic plasticity?
Synaptic plasticity refers to changes in the strength or number of synapses due to experience, learning, or injury, affecting how neurons communicate.
What is acetylcholine’s role in the nervous system?
Acetylcholine is involved in stimulating muscles, attention, arousal, memory, and motor control.
