A tissue is a group of similar cells and their intercellular materials in a discrete region of an organ performing a specific function. <span>There
are five levels of organization and these are the cells, tissues, organs, organ
systems and organism. The most complex is the organism having the rest of the
organization in it and the least complex is the cell, the basic unit of
structure. The human body tissue is an organized group of cells that is formed to create a muscle or an organ. There are four types of human body tissue: muscle, epithelial, connective and nervous tissue. Each function according to how they are grouped.</span>
Answer:
The pulmonary artery carries deoxygenated blood (blood whose oxygen content is relatively low) from the right ventricle to the lungs. The blood here passes through capillaries to alveoli and becomes oxygenated (as part of the process of respiration).
Plants do not breathe, they only respire. No such respiratory organ os present in plants. The carbon dioxide produced in animals during respiration is released to the atmosphere, whereas the carbondioxide produced during plant respiration may be used by the plant for carrying out photosynthesis.