<h3>Difference Between Artery and Vein
</h3><h3>
</h3><h3>Artery
</h3><h3>
</h3><h3>1. Vessels which carry blood from the heart to various body parts </h3><h3>2. Arteries carry oxygenated blood from the heart except pulmonary artery </h3><h3>3. Arteries have thick elastic muscular walls </h3><h3>4. Valves are absent </h3><h3>5. Blood flows under high pressure </h3><h3>Vein </h3><h3>1. Vessels which carry blood from the various body parts to the heart </h3><h3>2. Veins carry deoxygenated blood from the various body parts except pulmonary vein </h3><h3>3. Veins have thin non elastic walls </h3><h3>4. Valves are present to prevent the backward flow of blood </h3><h3>5. Blood flows under low pressure </h3>
Nitrogen because it is essential for making nucleic acids and amino acids in plants. Nucleic acids make DNA and RNA and amino acids make proteins. All are needed for cell growth and repair.