In answering this question I'll be referencing the college biology
text, "BIOLOGY," by Villee, Solomon & Davis,CBS College Publishing:
Here's the definition of a lysosome, from the above text, p.73:
"Membranous sacs containing hydrolytic enzymes."
Here's a more detailed description of lysosomes:
"Intracellular digestive enzymes are manufactured along the rough ER
and then transported to the Golgi complex. There the enzymes are in
enclosed in a bit of Golgi complex membrane, which is then pinched off
and separated from the Golgi. Each little vesicle containing digestive
enzymes is a lysosome."
As far as how the lysosome's function is important to the overall
health of a cell, there are two main points to consider:
1. Lysosomes are found throught the cytoplasm. "When a white blood
cell ingests bacteria or some other scavenger cell (e.g., a
macrophage) ingests debris or dead cells, this foreign matter is
surrounded by a vesicle consisting of part of the cell membrane."
2. "In a cell that is short of fuel, lysosomes may break down
organelles so that their component molecules may be used as fuel. This
sort of self-cannabalizing is termed autophagy (eating one's self).
When a cell dies, lysosomes release their enzymes into the cytoplasm,
where they break down the cell itself. This self-destruct system
acocunts for the rapid deterioration of many cells following death."
So, lysosomes both remove foreign material from a cell; during its
life, and self-destruct a cell shortly after its death.
From the following Emory University website:
"Lysosomes supply the enzymes for degradation of worn out cell parts
in a process called autophagy."
Here are some links to lead you to additional resources on this topic:
Google search strategy:
Additional search strategy:
Personal knowledge, BIOLOGY," by Villee, Solomon & Davis,CBS College Publishing
I hope this helps.
Good luck in continuing your inquiries!
Google Answers Researcher