Image Based Question-69903

All the following statements are true about the cell modification marked by “A” in the image except:

A. Shrinkage in cell size is due to reduction in cell organelles, chiefly mitochondria, myofilaments and endoplasmic reticulum.

B. There is often increase in the number of autophagic vacuoles containing cell debris

C. There is increased synthesis of DNA and RNA

D. Might be caused by loss of endocrine regulatory mechanism

Correct Answer » C Explanation

Ans:C. There is increased synthesis of DNA and RNA.

Atrophy is shown in the image.

ATROPHY

• Reduction of the number and size of parenchymal cells of an organ or its parts which was once normal is called atrophy (compared from hypoplasia which is the term used for developmentally small size, and aplasia for extreme failure of development so that only rudimentary tissue is present).

CAUSES.

Atrophy may occur from physiologic or pathologic causes:

A. Physiologic atrophy.

For example:

• Atrophy of lymphoid tissue in lymph nodes, appendix and thymus.
• Atrophy of gonads after menopause.
• Atrophy of brain with aging.

B. Pathologic atrophy.

• Starvation atrophy.
• Ischaemic atrophy.
• Disuse atrophy.
• Neuropathic atrophy.
• Endocrine atrophy.
• Pressure atrophy.
• Idiopathic atrophy. There are some examples of atrophy where no obvious cause is present e.g. i) Myopathies. ii) Testicular atrophy.

MORPHOLOGIC FEATURES.

• The organ is small, often shrunken. The cells become smaller in size but are not dead cells.
• Shrinkage in cell size is due to reduction in cell organelles, chiefly mitochondria, myofilaments and endoplasmic reticulum.
• There is often increase in the number of autophagic vacuoles containing cell debris .
• These autophagic vacuoles may persist to form ‘residual bodies’ in the cell cytoplasm e.g. lipofuscin pigment granules in brown atrophy