The build up of lactic acid will need oxygen to break it up. Lactic acid is why muscles feel tired after excess exercise
Oceans streams and rivers.............................
I believe it's oxygenated or oxygen rich blood away from the heart.
Sunspots are temporary phenomena on the Sun's photosphere that appear as spots darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. Sunspots usually appear in pairs of opposite magnetic polarity.
