Answer:
What sends oxygenated blood back to the heart from the lungs?
Oxygen-rich blood flows from the lungs back into the left atrium (LA), or the left upper chamber of the heart, through four pulmonary veins. Oxygen-rich blood then flows through the mitral valve (MV) into the left ventricle (LV), or the left lower chamber.
Explanation:
 
        
             
        
        
        
Answer:
Weathering and erosion, transportation, deposition, compaction and cementation, metamorphism, and rock melting.
Explanation:
The rock cycle has 5 main sections (igneous, sedimentary, sediment, metamorphic, and magma.) The rock cycle can go almost any way it wants. Its not like the water cycle were it goes in certain order.
 
        
                    
             
        
        
        
Answer: 
a trait is a characteristic, such as color or size, that is inherited by an offspring from its parents. The genes that control a trait come in pairs, one gene from each parent. If a gene pair contains a dominant allele, then the offspring will show this dominant trait.
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Books.. GOogle..Bing.... oh Wait BRAINLY
        
             
        
        
        
The cell organ that makes proteins is the ribosomes
hope this helps :)