level: Level 1
Questions and Answers List
level questions: Level 1
| Question | Answer |
|---|---|
| is the inability of the heart to meet the metabolic requirements of the peripheral system. Symptoms: Major symptoms include weakness, fatigue, and dyspnea | Congestive heart failure (CHF) |
| 1 an increase and growth of muscle cells. 2 restricted blood flow 3 relates heart performance to the size of the individual | 1 Hypertrophy 2 Ischemia 3 Stroke volume index (SVI) |
| Pathophysiology 1 Myocardial cell loss due to regional __ results in deterioration of systolic and diastolic performance. 2 When confronted by an increased load, the remaining normal heart __ to maintain adequate cardiac performance. 3 __ develop to maintain cerebral and coronary perfusion. | . 1 ischemia or myopathy 2 hypertrophies 3 Vasoconstrictor compensatory mechanisms |
| Vasoconstrictor compensatory mechanisms includes: | 1) Stimulation of the sympathetic nervous system 2) Stimulation of the renin-angiotensin system |
| 1 The __ of an unstimulated muscle cell is polarized—that is, the inside of the sarcolemma is negatively charged with respect to the outside. 2 The unstimulated state of the muscle cell, called the __, is created by the presence of large, negatively charged proteins and nucleic acids inside the cell. | 1 sarcolemma (plasma membrane) 2 resting potential |
| 1 A balance between K+ inside the cell and Na + outside the cell contributes to the __ 2 During an action potential, the balance of Na + and K + is upset so that the cell becomes __ | 1 polarization 2 depolarized. |
| Cardiac Muscle Contraction (in order) | 1 Rapid depolarization occurs when fast‐opening Na + channels in the sarcolemma open and allow an influx of Na + ions into the cardiac muscle cell. The Na + channels rapidly close. 2 A plateau phase occurs during which Ca 2+ enters the cytosol of the muscle cell. Ca 2+ enters from the sarcoplasmic reticulum (endoplasmic reticulum) within the cell and also from outside the cell through slow‐opening Ca 2+channels in the sarcolemma. the Ca 2+ channels open, K + channels, which normally leak small amounts of K + out of the cell, become more impermeable to K + leakage. 3 Repolarization occurs as K + channels open and K + diffuses out of the cell. At the same time, Ca 2+ channels close. These events restore the membrane to its original polarization, except that the positions of K + and Na + on each side of the sarcolemma are reversed. 4 A refractory period follows, during which concentration of K + and Na + are actively restored to their appropriate sides of the sarcolemma by Na +/K + pumps. The muscle cell cannot contract again until Na + and K + are restored to their resting potential states. |