<span>One group is given a larger dosage than is typically prescribed.
A second group is given a smaller dosage than is typically prescribed
Then results of the groups are compared to each other.
The thing that is missing in this experimental design is a third group who are tested with the typical dosage.</span>
        
             
        
        
        
Answer:
Abiotic
Explanation: Water is not a living thing, therefore water is an abiotic factor.
 
        
             
        
        
        
Answer:
The Animal cell is the most likely to contain Clathrin and specifically among the animal's type of cells is the <em>Mammalian Cell</em> 
Explanation:
Clathrin is simply the model gathering protein that coats transport vesicles during layer traffic. Its capacity to polymerize into a polyhedral cross section adds to association and arranging of necessary layer proteins during receptor-interceded endocytosis, organelle bio-genesis, and chose reusing pathways and corruption pathways. The morphology, structure, and organic chemistry of clathrin is portrayed with an emphasis on how these properties add to clathrin's cell capacities and their guideline. 
The collaborations of the clathrin light chain sub-units with actin-coordinating proteins and with the focal bit of the clathrin triskelion characterizes a part for these sub-units in contributing steadiness and solidarity to the clathrin grid, works that grow the collection of clathrin-moved freight and encourage a function for the clathrin cross section in getting sorted out the actin cyto-skeleton. With the revelation of a second type of clathrin in people and a non-layer traffic part for clathrin at the mitotic shaft, the variety of intra-cellular capacities attributed to clathrin proteins currently reaches out to explicit functions in human glucose digestion and in mitosis, notwithstanding traditional clathrin-intervened pathways.
 
        
             
        
        
        
Answer:
The correct answer would be d. thymus.
The thymus is a specialized lymphoid organ of an immune system.
It serves as the site for training and maturation of T-lymphocytes or T cells.  
It is composed two identical lobes each containing outer region termed as cortex and inner region termed as medulla.
T-cells are first trained and selected in the cortex region via positive selection. In this, T cells which are able to bind to foreign antigens are selected and rest are degraded.
The selected T cells then move in the medulla region where they are selected by negative selection. In this, the T cells which binds to self-antigens are degraded and rest survive to become functional T cells.