Drains blood from myocardium into right atrium

Coronary Sinus

Explanation:

A coronary sinus is a group of small veins that collectively from the sinus which is nothing but a large sized vessel. This sinus is located along the rear side of heart between the left ventricle and left atrium.  

This sinus collects cardiac venous blood which comes from the mycocardium and the thick muscle layer with in the heart and facilitates its movement to the right atrium.

answer; ///as energy flows through an ecosystem,energy (decreases) at each

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.