21 Cellular Changes During Aging
Cellular Plasma Membrane Changes
- As the cell ages the plasma membrane has an increases amount fatty acids.
- This structural change decreases the fluidity of the plasma membrane and reduces the transportation of ions, nutrients, amino acids, and proteins across the membrane.
Nuclear Changes
- As the cell ages cross-linkages form between the sulfur atoms on the DNA in the nucleus of the cells.
- This structural change condenses the DNA which decreases the synthesis of RNA, reduced the cells ability to repair enzymes, and may reduce the cell’s ability to divide.
Cytoplasmic Changes
- As the cell ages the volume of cytoplasm increases, enzymes that synthesize DNA move from the nucleus to the cytoplasm, and there is a gradual build up of lipofuscin.
- While it is unclear how this directly affects the cell, it is known that once the DNA migrates from the nucleus it is unable to synthesizes enzymes.
Ribosomal Changes
- As the cell ages the amount of ribosomal RNA and the number of ribosomes decreases.
- This structural change results in a decreased level of protein synthesis.
Mitochondrial Changes
- As the cell ages the number of mitochondrial present in a cell decreases.
- This structural change reduces the cell’s ability to produce energy.
Lysosomal Changes
- As the cell ages the lysosomes become less able to break down waste proteins, nucleic acids, carbohydrates, and fats.
- This results is a build up waste within the cell.