Because a<span>t some point during its life cycle, it had a dorsal hollow nerve chord, notochord, pharyngeal gill slits, and finally a muscular tail.
hope this helped and is right :)</span>
Myosin and actin protein filaments attach to each other . Calcium ions release into myofibrilles . Myosin filaments pull on the actin filaments
Answer:
Saudi Arabia, Russia, the United States, and Iran
Explanation:
<span>Stimulation of muscarinic receptors, a type of ACh receptor located in postganglionic synapses of the parasympathetic nervous system, would cause K+ channels to open, resulting in hyperpolarization of cardiac plasma membranes and a decreased heart rate.</span>
