physics chapter 3 section 3 Flashcards
Question
Answer
What is a synapse?
A synapse is a microscopic gap that separates the terminal buttons of one neuron from the receptors of another neuron.
How do neurons communicate across a synapse?
Neurons release chemicals (neurotransmitters) that travel across the synaptic gap to stimulate post-synaptic receptors.
What role do neurotransmitters play in the synapse?
Neurotransmitters are released from a nerve’s axon terminal, bind to receptors on the dendrite of the next neuron, and initiate an action potential.
What is a capacitor?
A capacitor is a passive two-terminal electrical component used to store energy in an electric field.
What happens when a capacitor is charged?
A potential difference is created between its plates, causing positive charge on one plate and negative charge on the other.
What does capacitance depend on?
Capacitance depends on the material, the area of the plates, and the distance between the plates.
What is the SI unit of capacitance?
The farad (F), named after Michael Faraday, is the SI unit of capacitance.
What is the function of a dielectric in a capacitor?
A dielectric is an insulating material that increases the capacitance and allows a higher voltage to be applied without breakdown.
How is the energy stored in a capacitor calculated?
Energy stored in a capacitor is given by the equation:E=12CV2E=21CV2, where C is capacitance and V is voltage.
What is Ohm’s law?
Ohm’s law states that current (I) is directly proportional to the potential difference (V) and inversely proportional to resistance (R), given byV=IRV=IR.
How do ions move across the cell membrane?
Ions move due to the concentration gradient and electrical gradient, which are described by Ohm’s law in terms of membrane potential.
What is an electrocardiogram (ECG or EKG)?
An ECG is a recording of the electrical activity of the heart, showing waves of depolarization (P wave, QRS complex) and repolarization (T wave).
