Which part of the heart encases the heart in a tough outer membrane?
A heartbeat produces the familiar "LUB-DUP" sounds as the chambers contract and the valves close. The first heart sound, "lub," is heard when the ventricles contract and the atrioventricular valves close. This sound last longest and has a lower pitch. The second heart sound, "dub," is heard when the relaxation of the ventricles allows the semilunar valves to close.
valves
left part of heart
It is a fibrosis (formation of scar tissue) in septum, a part of the heart that separates left and right part of the heart. It is usually a consequence of a viral infection.
rising action.
The axon is the part of the neuron that can propagate an action potential. This process relies on the opening and closing of ion channels along the axon membrane to allow the action potential to travel from the cell body to the axon terminals.
Action potential in the brain
Action potential in the brain
The axon hillock is the part of the neuron that is capable of generating an action potential. It integrates incoming signals from the dendrites and, if the threshold is reached, triggers the action potential to be propagated down the axon.
Negative
Action potentials are generated on a part of the neuron called the 'axon hillock' - the proximal most portion of the axon.
Heart
Positive
the longest part of the cell cycle is Interphase
The axon of a neuron is responsible for conducting an action potential. This is made possible by the presence of voltage-gated ion channels along the axon membrane that allow for the propagation of electrical signals.
The interphase is the longest.