In Tay-Sachs disease, a genetic mutation causes a malfunction in a certain organelle that leads to a backup of molecules and proteins, ultimately interfering with the entire functioning of the cell. Which organelle is primarily affected by this disease?

a. the nucleus
b. the Golgi apparatus
c. the endoplasmic reticulum
d. the lysosomes
e. the peroxisomes

In Tay-Sachs disease, lysosomes are affected.

Explanation: Tay-Sachs disease is a genetic disorder that destroys neurons in the nervous system (brain and spinal cord). Though rare, affected infants lose motor skills like sitting and crawling. Also, signs and symptoms are usually milder according to age as it can appear in childhood, adolescence or adulthood.

Tay-Sachs disease is caused by mutation in the HEXA gene which is responsible for making part of an enzyme called beta-hexosaminidase A. This enzyme plays an important role in the brain and spinal cord and is located in the lysosomes.