Question

Lysosomes are not helpful in
a. Osteogenesis
b. Cellular digestion
c. Metamorphosis
d. Lipogenesis

Answer 1

Lysosomes are electron microscopic vesicular structures of the cytoplasm that are involved in intracellular digestion activities, thus named lysosomes. Christian de Duve discovered these in the liver cells.

Complete answer:
- In animals, the number of lysosomes in the cell vary with the cell type. These are particularly abundant in certain white blood cells, macrophages, Kupffer’s cells, and in secretory cells of pancreas, kidneys, etc.
- Lysosomes arise from the Golgi bodies. Their membrane and hydrolytic enzymes are synthesized on the rough endoplasmic reticulum and are transported in the vesicles to the Golgi complex for modification and packaging.
- Secretory vesicles filled with lysosomal enzymes bud off from the Trans face of the Golgi complex and function as primary lysosomes.
- The lysosomes take part in several normal decomposition processes in a cell.
- They are present in the chondroblast cells and help in the osteogenesis process by replacing cartilage with bone.
- The hydrolytic enzymes present in the lysosome also help in digestion of materials. The organic substances taken up by the cells in vacuoles from the environment are digested in lysosomes and is called intracellular digestion. The foreign particles are also disposed of by hydrolyzing them in certain leukocytes and macrophages. This is called the natural defense of the body.
- Autolysis caused by the lysosomal enzymes plays an important role in the disappearance of the tail during metamorphosis of a frog's tadpole.
- Lipogenesis is the formation of lipids and it is not the function of lysosomes.

Hence, the correct answer is option (D).

Note: The lysosomes are called the suicide bag of the cell because of their autolytic role and disposable functions. These are also called recycling centers as they break down worn out cells and cell organelles to component molecules for building new cell organelles and cells.