Answer:
Explanation:
Pharmacophore (pharmacology) - The molecular framework responsible for a drug's biological activity. According to IUPAC — A pharmacophore is the ensemble of steric and electronic features that is necessary to ensure the optimal supramolecular interactions with a specific biological target structure and to trigger (or to block) its biological response. 
Privileged structures are defined as molecular frameworks which are able of providing useful ligands for more than one type of receptor or enzyme target by judicious structural modifications.
1) The 1,4-dihydropyridine ring is present in many biologically important molecules that acts as an important scaffold for cardiovascular drug - a calcium antagonists and although it is technically not considered as a pharmacophore, it is considered as a privileged structure.
1,4-Dihydropyridine (DHP), belongs to the class of calcium antagonist that inhibits the influx of extracellular Ca+2 through the L-type voltage-dependent calcium channels.
A positional substitution in the 4-position is feasible in the heterocyclic ring which in turn culminates in various calcium channel antagonist activities and this heterocyclic ring is the common feature for various pharmacological activities such as anti-inflammatory activity, analgesic activity,
 antihypertensive, antianginal, antitumor, antitubercular activity and antithrombotic .
Position on the heterocyclic ring binds to the L-type channel and also to N-type channel on membranes.
2.) The bioisosteres are not a suitable bioisostere for the traditional C-4 aryl or heteroaryl substitution which is necessary for calcium ion blockage thereby inhibiting it to function with the mechanism shared above.
 
        
             
        
        
        
I’m sorry but do you want me to answer all of these I just need a yes or no I’ll answer in the comments (:
        
             
        
        
        
Answer:
Abierto es sin vasos y cerrado es con vasos.
Explicación:
El sistema circulatorio abierto es un tipo de sistema que se encuentra en los invertebrados. en el que la sangre fluye libremente a través de las cavidades en lugar de los vasos sanguíneos mientras que, por otro lado, el sistema circulatorio cerrado es un tipo de sistema en el que el corazón bombea sangre y la sangre fluye a través de los vasos y capilares. Este tipo de sistema circulatorio está presente en humanos y vertebrados.
 
        
             
        
        
        
Hi! 
An example of a membrane would be Pericardium. This membrane in particular will cover the heart.
What is the Pericardium?
This membrane is a thin, double layered membrane which protects the heart from injuries as well as external blows.In between the membranes, there is a fluid known as pericardial fluid that is present. The function of this is to also protect the heart. 
Hope I could help!
-Peaculiar 
        
             
        
        
        
Hey there!!
For box X, the allele would have to be bc to match the data you have here.
I really hope this helps!!