Question

As lipids are transported into adipocytes, the adipocytes enlarge so that they can store more fat. Is this an example of hypertrophy or hyperplasia? Explain.

Answer 1

- Adipocytes are cells that store fats (lipids) within them. Enlargement of adipocytes to store more fat is an example of hypertrophy.

- Hypertrophy is an increase in the size of the cells that leads to enlargement of the cells but the number of the cells remains the same. Thus, to accommodate excessive fat in the body, the adipocytes undergoes hypertrophy and enlarges in size to store more fats within them. Increase in the number of cells is known as hyperplasia (cell size remains same in hyperplasia).

- Other examples of hypertrophy are :- growth of the uterus during pregnancy (although in pregnancy some amount of hyperplasia of uterine cells are also seen), left ventricular hypertrophy in patients of systemic hypertension, hypertrophy of smooth muscles of stomach in a condition known as pyloric stenosis where there is obstruction in the pylorus of stomach.  

- Examples of hyperplasia (increase in number of cells):- increase in the number of glandular cells of mammary glands during lactation, hyperplasia of uterine endometrium during proliferative phase of menstrual cycle under the influence of the hormone estrogen, hyperplasia of prostate gland in elderly males in response to androgens (a disease known as benign prostatic hyperplasia).