Describe the structure of the ovule and the formation of embryo sac​

answer; ///i do believe the answer is (virus);

your answer is "the 1950's"

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.