Question 12
(4 points) Each time the heart beats, changes in electrical potential occur on its surface that can be detected using metal contacts, which are attached to the skin.
The changes in potential are small, on the order of milivolts (mV) and must be amplified. The record of the potential changes for a given person’s heart is called an electrocardiogram (EKG or ECG) see a diagram belows. Just before the contraction of heart muscles, changes occur in the cell wall so that positive ions on the exterior of the cell are able to pass through the wall and neutralize those on the inside, or even make the inside surface slighty positive campared to the exterior. This depolarization, starts at one end of the cell and progresses toward the opposite end, until the whole muscle is depolarized. The muscle then slowly repolarizes to its original state. This whole process requires less than a second.
A. The equal but opposite charges on the two sides of a cell wall can be considered as a set of _________________
B. The metal contacts that are used to detect electrical potential changes are called as________________________________
C. What are X and Y marker in the EKG responding to the heart activities?______________________________
D. According to the diagram, how many beat per minute does the heart activity?_________________________________
The changes in potential are small, on the order of milivolts (mV) and must be amplified. The record of the potential changes for a given person’s heart is called an electrocardiogram (EKG or ECG) see a diagram belows. Just before the contraction of heart muscles, changes occur in the cell wall so that positive ions on the exterior of the cell are able to pass through the wall and neutralize those on the inside, or even make the inside surface slighty positive campared to the exterior. This depolarization, starts at one end of the cell and progresses toward the opposite end, until the whole muscle is depolarized. The muscle then slowly repolarizes to its original state. This whole process requires less than a second.
A. The equal but opposite charges on the two sides of a cell wall can be considered as a set of _________________
B. The metal contacts that are used to detect electrical potential changes are called as________________________________
C. What are X and Y marker in the EKG responding to the heart activities?______________________________
D. According to the diagram, how many beat per minute does the heart activity?_________________________________