Answer:Amphibians evolved during the middle of the Devonian period (416 to 359 million years ago) from the lobe-finned fish of the vertebrate class Sarcopterygii. Species within the genus Ichthyostega (members of the Labyrinthodontia subclass) are considered by some scientists to be the earliest amphibians.
Explanation:
Considering the choices;
A. blood glucose level and pH
B. amount of light and temperature
C. amount of light and pressure
D.
temperature and pH
Answer;
D.
temperature and pH
The two factors affect an enzyme's operation the most is the temperature and pH.
Explanation;
Enzymes work best at optimum pH and temperature.
At low temperature for example the enzymes are inactivated while at high temperatures enzymes are denatured.
At optimal temperature and pH; the chemical reaction rate is optimal.
The answer is Over-the counter.
Over-the-counter are medications sold without prescription. They got their name they are passed over the counter from the pharmacist to the patient. However, they, together with prescription and illegal drugs, are able to change the central nervous system.
Answer:
The time between the end of ventricular systole to the beginning of atrial systole is 100 ms or 0.1 seconds.
Explanation:
Ventricular systole is the removal of blood from the heart by pumping through aorta and pulmonary vein. Both aorta and pulmonary vein receive the blood from the heart. Aorta receives oxygenated blood and pulmonary vein receive deoxygenated blood, while atrial systole is the addition of blood into the ventricular from vena cava and pulmonary artery due to contraction of heart. This process occurs in 100 ms.
That he is to drunk to learn