How is a human sperm cell different from most other cells (i. e. simple squamous cell, a red blood cell and a smooth muscle cell) ?

Its reduced genetic content (haploid, n)

Explanation:

Cells are constantly being produced in our body. The body employs mitosis to keep on replicating these cells that constitute major organs or systems in our body. Humans are diploid organisms (2n) i. e. they contain two sets of chromosomes in their cells. When most of these cells divide by mitosis, they maintain the exact number of chromosomes. However, our reproductive/sex cells are not produced by mitosis, they use meiosis instead.

Reproductive cells in our body produce gametes using meiosis, which results in reduction in chromosomal number I. e. from diploid state to haploid state (n). This is done to ensure that the resulting individual from the fusion of these gametes are diploid.

Hence, one distinct difference between the sperm cell (sex cell) and other body cells in the male system is the number of chromosomes or genetic material contained in them.