Final answer:
Cells can atrophy due to inadequate nutrition, resulting in slowed down or stopped growth. Inactivity, starvation, and age-related factors can also lead to muscle atrophy.
Step-by-step explanation:
Cells can atrophy due to inadequate nutrition. When there is insufficient supply of dietary proteins, all cells lack amino acids for their synthetic activities and growth, resulting in slowed down or stopped growth. Inactivity and starvation can also lead to muscle atrophy, where skeletal muscle cells decrease in number and size due to lower protein content. Age-related muscle atrophy, known as sarcopenia, can be caused by a decrease in sensitivity to growth factors that are needed to maintain muscle mass.