Which of the following is immortal?
(a) Somatic cell
(b) Germ cell
(c) Glomerular cell
(d) Cells of pituitary

Options

A. Somatic cell
B. Germ cell
C. Glomerular cell
D. Cells of pituitary.

Answer

To determine which of the following cell types is considered "immortal," we will analyze each option provided in the question.

**Step 1: Understand the term "immortal" in cellular biology.**
- In cellular biology, "immortal" refers to cells that can divide indefinitely without undergoing senescence (the process of aging and dying). Immortal cells can replicate many times and are often associated with stem cells or certain types of cancer cells.

**Step 2: Analyze each option.**
- **(a) Somatic cell:** Somatic cells are the body cells that make up most of the tissues and organs. They have a limited lifespan and eventually undergo apoptosis (programmed cell death). Therefore, somatic cells are mortal.

- **(b) Germ cell:** Germ cells are responsible for producing gametes (sperm and eggs). They are considered undifferentiated and have the ability to divide indefinitely, similar to stem cells. This characteristic makes germ cells immortal.

- **(c) Glomerular cell:** Glomerular cells are part of the kidney's filtration system. Like somatic cells, they have a finite lifespan and eventually die, making them mortal.

- **(d) Cells of the pituitary:** The pituitary gland produces hormones and is made up of various cell types. These cells also have a limited lifespan and are mortal.

**Step 3: Conclusion.**
Based on the analysis above, the only cell type that is considered immortal is the **germ cell** (option b).

**Final Answer:** (b) Germ cell

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