The answer is B. The reason why is because natural selection causes changes in a populations over many generations, and in this case the change that is being made is the that the population is becoming immune to a disease.
Answer:
The answer is B
Explanation:
The thymus secretes thymosin, which is necessary for T cell production. Therefore, if the thymus were damaged, there would be a lower number of T cells in the blood
Q. The contraction cycle is triggered by the rise in ________ released from the sarcoplasmic reticulum (SR).
A. Ca2+
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I hope that helps you out!!
Any more questions, please feel free to ask me and I will gladly help you out!!
~Zoey
Answer:
Arousal theory
Explanation:
Arousal theory is a theory of motivation and according to this theory people are motivated to perform actions because they want to maintain an optimum level of physiological arousal. There is a unique arousal level for each person. When the arousal level drops below this level, the person seeks for some sort of stimulation in order to elevate it up to the optimum level.
The same is the case of Juan in the question. Sky diving gives him a unique level of arousal and for maintaining it he practices the diving even he is tired after a long day of work.
I believe the answer is a nanometer (which can measure wavelengths and such)
So B!