The black arrow marks which pigment?

The black arrow marks which pigment?

• A. Melanin
• B. Lipofuscin Pigments
• C. Hemosiderin
• D. Bilirubin

Answer: (B)

Lipofuscin is the aging, wear-and-tear pigment that builds up inside the lysosomes of long-lived cells, appearing as granular, yellow‑brown inclusions within the cytoplasm near the nucleus. The image shows these intracytoplasmic granules in a cell, which is characteristic of lipofuscin accumulation. This pigment is not produced by melanocytes or linked to iron stores, so it’s not melanin or hemosiderin, and it isn’t a bilirubin pigment from the liver. Lipofuscin’s perinuclear, lysosomal location and granular appearance in aging cells are the clues that point to it as the pigment marked by the arrow.

Lipofuscin is the aging, wear-and-tear pigment that builds up inside the lysosomes of long-lived cells, appearing as granular, yellow‑brown inclusions within the cytoplasm near the nucleus. The image shows these intracytoplasmic granules in a cell, which is characteristic of lipofuscin accumulation. This pigment is not produced by melanocytes or linked to iron stores, so it’s not melanin or hemosiderin, and it isn’t a bilirubin pigment from the liver. Lipofuscin’s perinuclear, lysosomal location and granular appearance in aging cells are the clues that point to it as the pigment marked by the arrow.