Final answer:
End-diastolic volume (EDV) is the amount of blood in the ventricles before ventricular contraction, while the end-systolic volume (ESV) is the amount of blood remaining in the ventricle after contraction.
Step-by-step explanation:
End-diastolic volume (EDV), also known as preload, is the amount of blood in the ventricles at the end of atrial systole just prior to ventricular contraction.
During ventricular systole, the ventricular muscle contracts, raising the pressure within the ventricle and pushing blood out of the heart. However, there is still some blood remaining in the ventricle after contraction, which is the end-systolic volume (ESV).
In a resting adult in a standing position, the EDV is approximately 130 mL, while the ESV is around 50-60 mL.