An organelle (a little organ) in a cell containing enzymes that degrade macromolecules (large molecules) and other items (such as bacteria) taken up by a cell during the process of endocytosis.
In endocytosis, macromolecules and particles outside the cell are taken up by the cell via a progressive invagination (inpouching) and eventual pinching off of a region of the cell membrane, forming a membrane-bound vesicle (bubble) within the cytoplasm of the cell.
The vesicle then fuses with the lysosome and the lysosomal enzymes carry out their appointed task of destruction (by hydrolysis). Amazingly, the lysosomal enzymes do not normally damage the cell itself.
Suffix having to do with lysis (destruction), as in hemolytic anemia, the excessive destruction of red blood cells leading to anemia.
- Long QT syndrome
A disorder of the heart’s electrical system that predisposes individuals to irregular heartbeats, fainting spells, and sudden death. The irregular heartbeats are typically brought on by stress or vigorous activity. Abbreviated LQTS. LQTS is often symptomless and undiagnosed, but it is well known as a cause of sudden cardiac death in young, apparently healthy people, […]
- Long arm of a chromosome
The long arm of a chromosome is termed the q arm. All human chromosomes have 2 arms, the p (short) arm and the q (long) arm. They are separated from each other only by a primary constriction, the centromere, the point at which the chromosome is attached to the spindle during cell division. The symbol […]
- Loneliness, fear of
“autos” (self) and “phobos” (fear). “Autos” has given us many English words such as “automatic” and “automotive” (self-moving) and “autonomy” (self-governing). And “phobos” has bequeathed us a vast number of phobias such as “claustrophobia” (fear of closed places) and “acrophobia” (fear of heights).
The portion of the lower back from just below the ribs to the pelvis.