Cell Biology and Neurophysiology Flashcards
What houses the insides of a cell?
The plasma membrane that is made up of a lipid bilayer
What is the purpose of the proteins in this housing?
The proteins are the link between extra and intracellular parts. They stabilize the membrane, selectively transport ions and large molecules, anchor the membrane to adjacent cells and substrates, help with cellular motility and communication.
How does a cell nucleus transport peptides or lipids?
A peptide or lipid is manufactured in the endoplasmic reticulum (ER), transported along the ER, modified and folded, properly folded proteins shuttles to cis of Golgi, additional modifications to medial and trans compartments, separated into distinct vesicles, and delivered to target site
What do mitochondria do?
Makes energy so that cells can be active manufacturing plants. Adenosine triphosphate (ATP) is the energy currency for the work we must do and is produced in the mitochondria using energy stored in food.
What is a neuron?
Neurons are the basic building blocks of the nervous system that communicate and send signals to other glands, muscles, and glial cells.
Can be afferent or efferent
Can sense changes to the internal environment and take corrective action to restore the internal environment to preset limits
What are the 4 zones of a neuron?
Input, action, transmission, output zone
An increase in discharge probability is what kind of input? Decrease?
Increase probability of discharge= excitatory input
Decrease in probability of discharge= inhibitory input
Axons are covered in what? Why?
Axons have a fatty covering called a myelin sheath, which insulates it to prevent diffusion of ions across the cell wall (electrical activity transmitted relatively slower)
What is a synapse?
Connection between neurons
How do the short lived mini-potentials generate an action potential?
Short-lived minipotentials include inhibitory postsynaptic potentials (IPSPs) and excitatory postsynaptic potentials (EPSPs). IPSPs and EPSPs sum and create a critical depolarization near the axon hillock, then an action potential is triggered.
Describe the voltage and transfer of chemicals in an action potential.
Action potentials begin when Na+ ions begin to flow from the preceding part of the axon; this increases the potential within the cell. Once the necessary threshold is reached, Na+ channels open which allow sodium ions to rush into the cell. This creates a more positive voltage in the cell in and results in a rapid rise in potential, which is the depolarization of the cell. The action potential is then propagated through the axon until it reaches the terminal buttons. As the action potential is propagated from the axon hillock, membrane capacitance becomes discharged in a spreading pattern. This allows for the depolarization and opening of the ion channels prior to the active region.
