Cellular waste in the human body
Lysosomes are membranous structures found inside animal cells that contain enzymes. These enzymes are responsible for digesting substances inside and outside the cell.
The cell reuses the substances resulting from the work of the lysosomes as fuel or to form new molecules. In other words, lysosomes also influence the growth and survival of the cell.
Lysosomes have a very acidic composition (with a pH of 5.0), so they are surrounded by a membrane to protect them from contact with the rest of the cell. They are composed of different types of enzymes that are responsible for digesting different types of substances. Some of these enzymes are:
Lysosomes originate from the Golgi apparatus, another cellular organelle that is responsible for sorting synthesized proteins that can be disintegrated in lysosomes, endosomes or in the plasma membrane. It is also responsible for distributing them to the rest of the organism.
What is cellular excretion
A: It is a way of eliminating “garbage” from your cells. It is a cleaning system, but also a recycling system. When that garbage is degraded, the materials that are obtained can be used to perform other functions. For example, I have an old chair that is no longer useful because it is broken or because I don’t like it. What I can do is take that chair and take pieces of wood out of it to make me a new shelf. That’s what autophagy does with cellular components.
“Autophagy is a way for cells to get rid of their “junk.” It is a cleaning system, but also a recycling system. The materials that are obtained can be used to perform other functions.”
A: A prototypical case is neurodegenerative diseases. In these diseases, toxins accumulate in neurons. Increasing autophagy in them allows that toxic material to be eliminated and recycled. We are focusing on therapies based on autophagy induction to treat these and other pathologies. Moreover, autophagy not only has applications in diseases, but also in other areas such as biotechnology or plant biology. All cells use autophagy, so there are many possibilities that it can be used to improve and solve challenges in various sectors.
What role does the cell membrane play in cell excretion?
Español: Diagram and images of autophagy from a 2006 PLoS Biology review. (A) Diagram of autophagy; (B) Electron micrograph of autophagic structures in the fatbody of a fruit fly larva; (C) Fluorescently labeled autophagosomes in liver cells of starved mice.
It is a process in which cytoplasm and organelles are sequestered in vesicles with a duplicated cell membrane, releasing their contents into lysosomes for subsequent degradation and recycling of macromolecules.
One of these sensors is the TOR (Target of Rapamycin) protein which inhibits autophagy in a nutrient-rich environment. Autophagy also has homeostatic and biosynthetic functions. For example in conditions in which peroxisomes are not needed, they are degraded through a specific type of autophagy called pexophagy. In addition, autophagy can promote a type of programmed cell death.
Oncosis serves to designate any cell death characterized by significant swelling, rupture of the plasma membrane, dilation of cytoplasmic organelles (mitochondria, endoplasmic reticulum and Golgi), as well as moderate chromatin condensation.
Cell excretion pdf
Viruses have evolved to reproduce inside the cell they infect, since on their own they are unable to do so because they lack the necessary molecular machinery. So, there are three problems that a virus must solve in order to make more copies of itself: 1) how to reproduce inside the cell it infects? 2) how to spread from one host to another? and 3) how to avoid being eliminated by the host’s defenses (immune system)?
In general, DNA viruses use parts of the host’s information, as well as part of its cellular machinery. The problem with this strategy is that most mature host cells are not actively replicating, they are resting to save energy. Therefore, DNA viruses need to find a way to activate the motor (“pass current”) of the host cell or, alternatively, bring with them the attachments of those cellular parts that are not active when the virus enters. Basically what viruses do to reproduce is to hijack the cell’s factory to produce viruses instead of new cells. On the other hand, RNA viruses bring with them their own genetic information copying machines (e.g. RNA-polymerase enzyme) or possess genes (genetic information) that produce the proteins required to assemble the copying machines inside the cell they infect, which makes them independent of the cellular machinery and capable of infecting cells that are not actively reproducing.