A third way that gene duplicates arise is by retrotransposition.

Here the messenger RNA from a gene is reverse-transcribed to DNA, which is then integrated into the genome.

TLS Online TPP Program

#Id: 5319

#Unit 7. System Physiology – Animal

Reduced Ventricular Ejection

Because the aortic valve is still open, blood continues to be ejected from the left ventricle into the aorta, albeit at a reduced rate.

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#Id: 5320

#Unit 7. System Physiology – Animal

Reduced Ventricular Ejection

Left atrial pressure continues to increase as blood returns to the left heart from the lungs.

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#Id: 5321

#Unit 7. System Physiology – Animal

Reduced Ventricular Ejection

the ventricles begin to repolarize, which is marked by the beginning of the T wave on the ECG.

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#Id: 5322

#Unit 7. System Physiology – Animal

Isovolumetric Ventricular Relaxation

Left ventricle is relaxed

Left ventricular pressure decreases

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#Id: 5323

#Unit 7. System Physiology – Animal

 Isovolumetric Ventricular Relaxation

When left ventricular pressure falls below aortic pressure, the aortic valve closes.

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#Id: 5324

#Unit 7. System Physiology – Animal

Isovolumetric Ventricular Relaxation

Closure of aortic valve producing the second heart sound (S2).