The drawings below represent two cell types from a pig. The epithelial cell is found in the small intestine, and the cardiomyocyte is found in the heart.

 Because of differential gene expression, the epithelial cell and the cardiomyocyte produce different proteins.

(Choice B) B Because the cells are the result of a fertilization event, the epithelial cell and the cardiomyocyte contain different chromosomes.

Because the cells have undergone mitosis, the epithelial cell and the cardiomyocyte contain different genes.

The diagram below shows a cell moving from one phase of mitosis to another.

Chromosomes extend from the poles of the cell to attach to the structures that have aligned at the center.

The nucleus disappears, and sister chromatids move about freely in the cell.

The nuclear envelope breaks down and chromosomes align at the center of the cell.

In cats, fertilization occurs when a haploid sperm cell and a haploid egg cell fuse.

A cat begins as a single diploid cell. This cell undergoes mitosis to grow into a cat made of many diploid cells.

A cat begins as a single diploid cell. This cell undergoes mitosis to grow into a cat made of many haploid cells.

A cat begins as a single haploid cell. This cell undergoes mitosis to grow into a cat made of many diploid cells.

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One cell becomes two, two cells become four, yada yada yada... Elephant!

Cell Division & Organism Growth