Homeostatic control mechanisms Require an afferent pathway informing a control center of a change in the environment. Keep levels of substances such as 02 and glucose exactly constant at all times in the blood. Are feed-forward mechanisms, with no feedback involved. Always attempt to increase the magnitude of the original stimulus.

n the context of neuronal function, nerve action potentials are generated when: Multiple Choice CI- ions influx through chloride channels to hyperpolarize the nerve membrane. Na+ ions influx through sodium channels to depolarize the nerve membrane. CI- ions influx through chloride channels to depolarize the nerve membrane. Nat ions influx through sodium channels to hyperpolarize the nerve membrane. < Prev 24 of 25 Next

A patient with chronic right shoulder pain has learned that the use of imagery and guided meditation has helped control his pain. A family member asks how these techniques can help with pain. The nurse replies that these therapies can slow the release of transmitter chemicals in the dorsal horn change the cognitive and affective thoughts about the pain prevent transmission of nociceptive stimuli to the brain increase the modulating effect of the efferent pathways

Extracellular recordings create a distinct action potential. Choose the option that best describes the trace recording after stimulation.    1.The voltage trace becomes increasingly positive because the extracellular space becomes less negative 2.The voltage trace becomes increasingly positive because the extracellular space becomes less positive 3.The voltage trace becomes increasingly negative because the extracellular space becomes less positive 4.The voltage trace becomes increasingly negative because the extracellular space becomes more positive

How would antibodies against nicotinic acetylcholine receptors (nAChRs) affect the influx of sodium (Na+) into a skeletal muscle cell?  Group of answer choices These antibodies would target nAChRs for destruction leading to lower sodium influx in muscle cells. These antibodies would target nAChRs, changing their shape to allow calcium instead of sodium through. These antibodies would target nAChRs, changing their shape to allow only potassium through. These antibodies would target nAChRs aiding acetylcholine in its binding to receptors, leading to increased sodium influx in muscle cells.  pick one answer

Students in a veterinary school are given the following hypotheticalproblem: A dog ingests organophosphate poison, and the students areresponsible for saving the animal’s life. Organophosphate poisons bindto and inhibit acetylcholinesterase. Several substances the studentscould inject include the following: acetylcholine, curare (which blocksacetylcholine receptors), and potassium chloride. If you were a studentin the class, what would you advise to save the animal?

Match the body temperature control item to the appropriate location in the negative feedback loop. Effector when variable is low Effector when variable is high Control center Sensor Controlled variable   A. Muscles for shivering and goosebumps B. Nerves in skin C. Brain D. Sweat glands E. Temperature

Which of the following statements is FALSE? (Choose the best answer) O Neurons in the nervous system use electrical and chemical synapses to communicate between neurons and their target cells. Chemical synapses allow presynaptic neurons to excite or inhibit the postsynaptic neurons. O Electrical synapses allow presynaptic neurons to excite or inhibit the postsynaptic neurons. O Electrical synapses allow direct exchanges of both electric current and cytoplasmic contents. A single neuron uses either the electrical or chemical synapses to communicate with its target cells.

Which component of a homeostatic control mechanism would the life function "responsiveness" be best associated with? O effector O gland O receptor O muscle none of the above Next ► « Previous

The patient's muscle weakness, dizziness, and nausea are all due to hypokalemia. How does hypokalemia lead to muscle weakness? O hypokalemia leads to hypopolarization which results in fewer action potentials arriving at skeletal muscles O hypokalemia leads to hyperpolarization which results in fewer action potentials arriving at skeletal muscles O hypokalemia leads to hypopolarization which leads to too many action potentials arriving at skeletal muscles O hypokalemia leads to hyperpolarization which results in too many action potentials arriving at skeletal muscles