Homeostasis Flashcards
What is a monitor component?
Special sensors that detect changes in stimuli
What is the coordinating Center component?
Receive signals from sensors. Acts as a control center where it’s at the range within which a variable should be maintained. Relays information to the regulator
What is the effector component?
Response to signals which restores the system to normal
What is a positive feedback system?
System that amplifies a small change to accomplish a task fast. This is less common in the body. An example is childbirth
What is a negative feedback system?
Process to restore conditions their original state. It ensures that small changes don’t become too large. An example is body temperature
What is thermoregulation?
Maintaining a body temperature within the range that enables a cell to function efficiently. Organisms Thermoregulate differently.
What are the parts of a neuron?
Dendrites are branching projections that conduct impulses to cell body of the neuron, there’s a cell body and a nucleus, the axon is an elongated projection that conducts nerve impulses away from the cell body of a neuron, there is a nerve ending
What is a sensory neuron?
Conduct impulses to the central nervous system
What is a motor neuron?
Conduct impulses away from the central nervous system towards muscles and glands
What are interneurons?
Conduct impulses from sensory neurons to motor neurons
What are glial cells?
Support cells, bringing the cells of nervous tissue together structurally and functionally
What is MS?
Characterized by myelin loss in central nerve fibers and resulting conduction impairments
What is a reflex?
Rapid predictable and involuntary responses to stimuli
What is the reflex arc?
Direct route from a sensory neuron to an interneuron to an effector
What are nerve impulses?
Self propagating wave or electrical disturbance that travels along the surface of a neuron membrane. Sometimes called action potentials
What is a threshold level?
Minimum level of a stimulus required to produce a response
What is the all or none response?
Never responds completely or not at all
What are the four steps to stimulating and nerve?
Neurons at rest, exciting a nerve impulse, returning to rest, nerve impulse propagation
Describe the first step to stimulating a nerve?
There is an electrochemical difference that exists between the inside and outside of the cell, this is called polarization. At rest the neurons membrane is slightly positive on the outside from a slight excess of sodium ions this is known as the resting potential
Describe the second step to stimulating a nerve
Stimulus indicates response by receptor this is known as excitation. Inward movement of the sodium ions depolarizes the membrane by making the inside more positive, this is called depolarization. This nerve impulse called the action potential is propagated over the entire axon.
Describe the third step to stimulating a nerve
The stimulated section of the membrane immediately repolarizes. Repolarization occurs through the sodium potassium pump restoring the original configuration. This requires ATP
Describe the fourth step to stimulating a nerve
Nerve impulse propagation, moves in one direction self propagating action potential result down acts on like a wave
What is continuation of nerve impulse?
Axons and in terminals where they are separated from the next neuron by a gap called synapse. Impulses are able to cross the synapse to another next. Neurotransmitters are released from the axon to bind to specific receptor molecules on the dendrite of the next neuron
What is the synapse?
The place where impulses are transmitted from one neuron to another
