Garstang's Auricularia hypothesis suggests that ancestral vertebrates may have evolved from urochordate larvae.
What is Garstang's Auricularia?
The auricularia hypothesis, proposed by Garstang was an attempt to explain how the chordate body plan originated from a deuterostome common ancestor by emphasizing the significance of changes in larval forms. According to the Garstang Hypothesis, development of sexual maturity in a non-metamorphosing lineage of tunicates might provide the immediate proto-chordate ancestors of more typical chordates.
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Answer:
The best answer to the question: These cellular structures are utilized in strong involuntary muscle contractions and transmission of electrical impulses, would be: T-Tubules.
Explanation:
In both skeletal and cardiac muscle, not smooth muscle, because of the way that the muscle fibers are conformed into tight bundles of sarcomeres (skeletal muscle) and myocardiocytes (cardiac muscle), there is a need for a series of structures that will ensure that when there is a stimulus from the nervous systems, these stimulus will propagate to all the cells in the fibers, and not just one. 
Aside from counting with a neuromuscular motor plate, which will receive the neurotransmitter from the nerve endings and produce the appropriate reactions, as well as propagate that reaction to all the cells that are being stimulated, muscle fibers also have a structure known as T-Tubules. T-Tubules are formations much like roadways of cell plasma membrane that connect not just one, but all the cells within a muscle fiber so that once a stimulus comes, all the cells will initiate the process of calcium release and action potential propagation. These T-Tubules will ensure that electrical impulses reach all muscle cells and that all cells react at the same time as needed.
 
        
             
        
        
        
Answer:
I think B and D
Explanation:
A moraine is a mass of rocks and sediment carried down and deposited by a glacier, typically as ridges at its edges or extremity.
 
        
             
        
        
        
true, certain bacteria can survive in places like the dead sea and other high pH climates 
 
        
                    
             
        
        
        
Answer:
3 1 2
Explanation:
simple organisms apeared first insects would be less complicated than fish the came sharks as they are more complex organisms also insects were first to be food for fish and fish food for sharks