Answer: D. Species
Explanation:
Species is a group of population in which organisms have many common characteristics and they are capable of interbreeding and producing viable fertile offsprings. The members belonging to the same class and phylum have less common characteristics if they interbreed they may not produce viable fertile offsprings. Also, the organisms of the same kingdom have least common characteristics and will not have viable fertile offsprings after interbreeding.
Answer:
A. temperature of the reaction
B. amount of enzyme
E. pH of the reaction
Explanation:
Temperature should be kept constant because enzymes operate at different activity rates depending on the temperature. The same goes for the pH as well with different enzymes having different optimal pH levels.
The amount of enzyme should be kept constant as well because different concentrations of enzymes can determine how fast the reaction will occur.
Essentially anything that could affect enzyme activity apart from substrate concentration should be kept constant.
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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