Answer:
a. Aminopeptidase and e. Angiotensin converting enzyme (ACE)
Explanation:
Posttranslational modification includes the transfer or removal of functional groups. 
 
        
             
        
        
        
Answer:
Integrin molecules serve as stable, permanent anchors that anchor a cell to the extracellular matrix.
Explanation:
Integrins are transmembrane protein receptors that attach the cell cytoskeleton to the extracellular matrix (ECM) in animal cells. These glycoproteins (integrins) are highly dynamic heterodimeric molecules that anchor cells in their position and transduce signals into and out of cells. Integrin-ligand binding activates signaling pathways that are involved in fundamental cellular functions including, among others, organization of the cell cytoskeleton, cell migration, regulation of the cell cycle, etc.
 
        
             
        
        
        
One
substance, other than the secretions from nerve cells, that is used in cell
communication are hormones.
 
<span>
To
add, <span>a hormone is any member of a class of signaling
molecules produced by glands in multicellular organisms that are transported by
the circulatory system to target distant organs to regulate physiology and
behaviour.</span></span>
        
             
        
        
        
The answer is NAD+.
NAD+ is the primary oxidizing agent in the glycolytic pathway. Oxidizing agents gain electrons and thus, they are reduced in a reaction. In the glycolytic pathway, NAD+ server the oxidizing agent. It accepts electrons from the molecules, such as some intermediates of the glycolytic pathway. As the result, it is reduced to NADH which can serve in some reactions as a reducing agent.