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Lysosomes contain several digestive enzymes which when released bring about the breakdown of various cytoplasmic structures. If these enzymes are released freely in the cell, they would result in auto digestion of the cell itself. Therefore, they are called suicidal bags of the cell. . . .
Plants and bacteria can synthesize all the vitamins. Animals depend on plants or other animals for vitamins. Only Vitamin D and K can be synthesized in our body. Sunlight act on the fat which lie below the skin to form Vitamin D. Bacteria in our intestine synthesize vitamin K, B3, B6 and B12. Vitamin A, D< E and . . .
Kidney transplant and dialysis If both kidneys in a person stop functioning, kidney transplantation can be carried out to save the life of the person. For this a functional kidney is received from a suitable donor and transplanted into the patient. Thus both the donor and recipient can survive on one kidney each. When both the . . .
Retrovirus All viruses are pathogenic. They are responsible for several diseases. In all living organisms, DNA is hereditary material. But in some viruses hereditary material is RNA. Such viruses are called retroviruses. HIV and mums viruses in animals, and TMV in plants are retroviruses. . . .