Answer:
The lunar phases gradually change over the period of a synodic month (about 29.53 days), as the orbital positions of the Moon around Earth and of Earth around the Sun shift. The Moon's rotation is tidally locked by Earth's gravity; therefore, most of the same lunar side always faces Earth.
Explanation:
 
        
             
        
        
        
The sequence of impulse through the cardiac conduction system starts from SA node passes to AV node to atrioventricular bundle fibers and finally to Purkinje fibers. 
Heart is an organ that receives oxygenated blood form lungs and deoxygenated blood from different parts of body. Oxygenated blood is transported to different organs and deoxygenated blood is transported to lungs for oxygenation.
Now, to perform this transportation, the auricles and ventricles of heart contract and relax. In order to contract and relax, impulse generation is required, which begins at SA node or Sinoatrial node. It is also referred to as pacemaker of the heart. SA node contracts the atria and the impulse transfers to AV node or Atrioventricular node. 
This is followed by transfer of impulse to atrioventricular bundle fibers which further passes it on to Purkinje fibres for ventricular contraction. Now the blood is sent to lungs and aorta as per it's oxygen status. 
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That fact can be explained by the similarity in their genes. 
Dogs and coyotes are from the same class, family and genus (Mammalia, Canidae, Canis). 
This is almost enough for their offspring to be viable. But if the DNA is similar (which it is) offspring the chances of viable and fertile offspring is high almost at 100%.
Hope it helped,
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Answer:
C. Synthesis of organic molecules
Explanation:
According to chemical evolution theory, life originated from inorganic molecules by the mode of chemical evolution. In primitive conditions of earth, only inorganic molecules were present. These molecules reacted under lightning, UV radiation and other environmental conditions to give rise to complex organic molecules like amino acids, sugars, lipids etc. They formed the basis for proteins, RNA and other molecules which ultimately led to the formation of cellular structures.