Question

Which cells are considered immortal?
neurons
blood cells
cardiac muscle cells
stem cells

Answer 1

Of the list, stem cells are the ones considered (effectively) immortal — they can self-renew many times and, especially embryonic/germline stem cells or cultured stem-cell lines, maintain replicative capacity via telomerase.

- Neurons and cardiac muscle cells are largely post‑mitotic: they don’t divide (they’re long‑lived but not immortal).
- Blood cells (most mature blood cells) are short‑lived and regularly replenished by hematopoietic stem cells.
- Note: cancer cell lines (e.g., HeLa) and germline cells also show “immortal” behavior because they maintain telomeres/telomerase.