Nervous System and Homeostasis

These flashcards cover key vocabulary related to the nervous system and the concepts of homeostasis, helping to solidify understanding of the material for the upcoming exam.

Homeostasis

The ability to maintain a constant internal environment in the body.

Negative Feedback

A process in which the body senses a change and reacts to reverse the condition.

Positive Feedback

Self-amplifying cycles that initially cause a greater change before returning to normal.

Neurons

Specialized cells that make up nervous tissue, responsible for transmitting signals.

Dendrites

Projections of the soma that receive signals from other neurons.

Axon

Extension away from the soma that transmits electrical signals to other cells.

Myelin

Insulating sheath around axons that ensures efficient transmission of electrical impulses.

Central Nervous System (CNS)

Consists of the brain and spinal cord; site of integration of sensory input.

Peripheral Nervous System (PNS)

Everything that comes off of the brain and spinal cord, including nerves that innervate the body.

Resting Membrane Potential (RMP)

The electrical potential difference across the plasma membrane of a neuron at rest, approximately -70mV.

Electrochemical Gradient

The combined gradient of chemical concentration and electrical charge that drives ion movement across the membrane.

Graded Potentials

Local, small changes in voltage that occur in the dendrites and cell body, can lead to action potentials.

Action Potentials

All-or-nothing signals triggered when graded potentials reach a threshold, propagating along the axon.

Depolarization

The process by which the inside of a cell becomes more positive, moving towards the threshold.

Hyperpolarization

The process by which the inside of a cell becomes more negative, moving away from the threshold.