False! Primary succession is when a community has to completely start over which takes a long time.
There are different chemical agents which are used to study the heart rate of frog. Generally Ringer's solution is used to study frog's heart simulation. At different temperature, frogs heart speeds up or slows down while using Ringer's solution at experiment. Ringer's solution is mixture of salt solution which comprises of NaCl, KCl, CaCl2 and Na2CO3. Sometimes other chemicals like MgCl or antibiotics are also used as addition in Ringer's solution.
This solution is chiefly used to study in vitro experiments on organs and tissues like frog's heart.
Ringer's solution at 23 degree Celsius for normal heart rate
Ringer's solution at 32 degree Celsius, heart rate speed up and
Ringer's solution at 5 degree Celsius, heart rate slows down.
other chemicals also have significant effect in heart rate,
For example, Calcium ion in excess will slow down the heart rate, Atropine increases heart rate and digitalis slows down the heart rate.
Complete question is;
When the concentrations of reactant molecules are increased, the rate of reaction increases. The best explanation for this phenomenon is that as the reactant concentration increases,
A)the average kinetic energy of molecules increases.
B)the frequency of molecular collisions increases.
C)the rate constant increases.
D)the activation energy increases.
E)the order of reaction increases.
Answer:
B) The frequency of molecular collisions increases.
Explanation:
When we increase number of reactant molecules, the effective collision between the reactant molecules will form a product which also increases. As a result, the overall rate of the reaction will also increase which means the frequency of the molecular collision will also increase as well.
Thus, the correct answer is Option B