Tag: excretion in living organisms

Many plants store waste materials in the vacuoles of mesophyll cells and epidermal cells. When old leaves fall, the waste materials are excreted along with the leaves.

Plants get rid of water by transpiration. Waste products may be stored in vacuoles or may be stored in leaves which fall off. Resine and gums are stored in xylem which are harmless to trees. When the leaves and bark are shed, the wastes are eliminated. Thus, option C is correct. 

The waste products in the plants are stored by the vacuoles which is centrally located in a plant cell. It is filled with waste products until  the plant dies, it does not "excrete" any sort of waste. Plants also eliminate waste by its accumulation in the vacuoles of the aged leave cells which gets removed when such leaves are shed off. This process is called abscission. The excretory products include resins, gums, latex etc. Peeling of bark can also be considered as one of the excretory processes of plants.

Unlike animals, plants do not have specialized excretory organs. Excess carbon dioxide and oxygen are excreted from the plant through the stomata in the leaves. 

Deciduous trees are those that shed their leaves once in a year and new leaves are grown. these are also known as the evergreen trees.

In animals, the main excretory products are, Ammonia- protozoans, crustaceans, platyhelminths, cnidarians, poriferans, echinoderms, fishes, larvae/tadpoles of amphibians are ammonotelic. Urea -cartilaginous fish, few bony fishes, adult amphibians and mammals including humans are uricotelic, Uric acid-terrestrial arthropods (including insects), lizards, snakes, and birds are uricotelic.