In this task, you are given a question and answer options for that question. Using this information, you have to classify each text into different topics: medicine, nursery, psychology, chemistry, pharmacology, biology.

[Q]: Question: Kinesin and dynein are: 
 Options:  <0> Adhesion proteins. <1> Microtubular motors. <2> Degradative enzymes <3> Components of the vesicular cover. <4> Transcriptional factors.
[A]: biology


[Q]: Question: The standard free energy of activation of a reaction is: 
 Options:  <0> The difference in free energy between the basal state of the products and the substrates. <1> The difference of the enthalpy minus the entropy of the system. <2> The basal energy of the substrates in a catalyzed reaction. <3> The additional free energy that molecules must reach to reach the state of transition. <4> The energy released from a catalysed reaction.
[A]: chemistry


[Q]: Question: The microvilli contain a beam of: 
 Options:  <0> Microtubules <1> Actin filaments. <2> Intermediate filaments <3> Spectrine <4> Collagen fibers.
[A]:
biology