Answer:
Explanation:
1- the purpose of blood flow-circulatory system- is to convey Oxygenated blood, oxygen bonded with haemoglobin in the RBC with Nutrients - and distributed these through the arteries and capillaries away from the heart, to reach the cells and tissues, and transported the wastes of theses cells and tissues , with C02 through the veins back to the heart and the kidney.
2. During diastole,deoxygented blood from the inferior and superior vena cavae entering the R.atrium, passes through the tricuspid valve into the Right Ventricle. Simultaneously, oxygenated blood returning through the pulmonary veins enters the left Atrium,emptied through the bicuspid valve into the Left.Ventricle.
During systole, the two ventricles contracts. The Right ventricle contracts, the pressure of the blood forces the tricuspid valve to close,and therefore de -oxygenated blood pushes the pulmonary valves to open and blood passes through the pulmonary artery to reach the lungs where exchanges of oxygen with carbon dioxide occurs.The blood is now oxygenated and returns to the left atrium via pulmonary veins.
Simultaneously, the left ventricle contracts,the oxygenated blood it contains forced the bicuspid valve to close so that blood is forced through the aortic valve to empty into the aorta into the systemic circulation,branches of the carotid artery supplies the heart from the aorta.
The Whole cycle continues.
The answer is A:
The SUGAR-PHOSPHATE CHAINS form the sides, and the BASE PAIRS form the rungs
Answer:
No, they are not. The concept of human races appears to be solidly grounded in present-day biology and our evolutionary history. But if you asked that conference of geneticists to give you a genetic definition of race, they wouldn’t be able to do it. Human races are not natural genetic groups; they are socially constructed categories. Genes certainly reflect geography, but unlike geography, human genetic differences don't fall along obvious natural boundaries that might define races.
Cant tell you the types, but they form from the weather elements, from being compressed, etc
For air masses to form fronts, they must collide with each other. B.