QRS complex refers to the combination of the Q, R, and S waves, and indicates ventricular depolarization and contraction (ventricular systole).
Ventricular rate can be calculated by determining the time interval between QRS complexes. The duration of the QRS complex is normally 0.06 to 0.10 seconds. This relatively short duration indicates that ventricular depolarization normally occurs very rapidly.
P QRS and T waves in electrocardiogram signifies the P wave in an ECG complex indicates atrial depolarization. The QRS is responsible for ventricular depolarization and the T wave is ventricular repolarization.
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A specific type of physical change is a phase change
Fossil record of the first possible bipeds is the evidence exists that state humans are evolved in Africa. Modern humans arose in Africa at least 250,000 to 300,000 years ago, fossils and DNA are the evidence that reveals. Scientists have been unable to pinpoint a more specific homeland because the earliest Homo sapiens fossils are found all across Africa.
Humans first evolved in Africa, and much of human evolution occurred on that continent. The fossils of early humans who lived between 6 and 2 million years ago come entirely from Africa. Most scientists currently recognize some 15 to 20 different species of early humans found from Africa.
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A compound light microscope is a microscope with more than one lens and its own light source. In this type of microscope, there are ocular lenses in the binocular eyepieces and objective lenses in a rotating nosepiece closer to the specimen.
Answer: Mitochondria
Explanation:
Mitochondria are rod-shaped organelles bounded by a double membrane in which the inner membrane is folded and filled with matrix. Mitochondria is present in both plant and animal cells, and serves as the power house where respiration occur and energy is released from the oxidation of simple sugar.