Answer: Four pulmonary veins.
Explanation: Oxygen and nutrient rich blood will flow from the lungs back into this part called the left atrium (Or as some will call it, the left upper chamber in the heart). From there, it goes through four pulmonary veins.
Hope I could help! :)
Yes plants do have a circulatory system haha
Called solar system because Sun is biggest and heaviest. Solar means sun planets revolve about (travel in circles around) the sun path a planet travels is called its orbit earth is the 3rd closest planet to the sun all the planets go around in the same direction (like clockwise or counterclockwise), in roughly the same plane, but at different speeds planets close to sun move fast, far out move slower closer a planet is to the sun, the hotter it is, more or less.
Answer:
none of these codons
Explanation:
In order for mutation to occur to form methionine codon from an isoleucine codon, position 3 must be changed to a G, giving AUG. A secind mutation would then be required at a second site in the AUG codon. since the isoleucine codons, AUA, AUC and AUU does not have a G at position 3, a true reversion can't occur without mutating the position 3 again.