B. The Threshold describes the minimum level of stimulus required to ctive a neuron. Hope that helps
Answer: The SA node
Answer choices are:
<span>A. </span>The AV node
<span>B. </span>The SA node
<span>C. </span>The purkinje fibers
<span>D. </span>The AV bundle
The SA node<span> is the heart's natural pacemaker consisting of a cluster of cells located in the upper part of the wall of the right atrium. (the right upper chamber of the heart). The electrical impulses are produced and sent out from there to regulate heartbeat. This is also called the sinus code. </span>
False. Evaporation is a physical change it is not a chemical change. It is a physical change because it is going from the liquid phase to the gas phase. It is not a chemical change because it is still made of two hydrogen atoms and an oxygen atom.
Answer:
Plucking...happens when glaciers pull rocks from the earths surface
So I believe that your answer would be 3
Explanation:
Plucking is removal of entire chunks of rock. Courtesy of Rocky Mountain National Park. Glaciers can shape landscapes through erosion, or the removal of rock and sediment.
Hope this helps:)
Answer:
Since there are fewer individuals there is less genetic variation meaning that one disease/disaster and wipe out the whole population
Explanation:
