Q. Lysosome is formed from which of the following cell organelles?
a) Nucleus
b) Endoplasmic reticulum
c) Golgi bodies
d) Ribosomes
Lysosome enzymes are made by proteins from the endoplasmic reticulum and enclosed within vesicles by the Golgi apparatus. Lysosomes are formed by budding from the Golgi complex.
Late endosomes fuse with transport vesicles from the Golgi that contain acid hydrolases. Once fused, these endosomes eventually develop into lysosomes.
Some cells, such as white blood cells, have many more lysosomes than others. These cells destroy bacteria, dead cells, cancerous cells, and foreign matter through cell digestion. Macrophages engulf matter by phagocytosis and enclose it within a vesicle called a phagosome. Lysosomes within the macrophage fuse with the phagosome releasing their enzymes and forming what is known as a phagolysosome. The internalized material is digested within the phagolysosome. Lysosomes are also necessary for the degradation of internal cell components such as organelles. In many organisms, lysosomes are also involved in programmed cell death.
a) Nucleus
b) Endoplasmic reticulum
c) Golgi bodies
d) Ribosomes
Answer: Golgi Bodies
Lysosomes: Cell Organelles
There are two primary types of cells: prokaryotic and eukaryotic cells. Lysosomes are organelles that are found in most animal cells and act as the digesters of a eukaryotic cell.What Are Lysosomes?
Lysosomes are spherical membranous sacs of enzymes. These enzymes are acidic hydrolase enzymes that can digest cellular macromolecules. The lysosome membrane helps to keep its internal compartment acidic and separates the digestive enzymes from the rest of the cell.Lysosome enzymes are made by proteins from the endoplasmic reticulum and enclosed within vesicles by the Golgi apparatus. Lysosomes are formed by budding from the Golgi complex.
Lysosome Enzymes
Lysosomes contain various hydrolytic enzymes (around 50 different enzymes) that are capable of digesting nucleic acids, polysaccharides, lipids, and proteins. The inside of a lysosome is kept acidic as the enzymes within work best in an acidic environment. If a lysosome's integrity is compromised, the enzymes would not be very harmful in the cell's neutral cytosol.Lysosome Formation
Lysosomes are formed from the fusion of vesicles from the Golgi complex with endosomes. Endosomes are vesicles that are formed by endocytosis as a section of the plasma membrane pinches off and is internalized by the cell. In this process, extracellular material is taken up by the cell. As endosomes mature, they become known as late endosomes.Late endosomes fuse with transport vesicles from the Golgi that contain acid hydrolases. Once fused, these endosomes eventually develop into lysosomes.
Lysosome Function
Lysosomes act as the "garbage disposal" of a cell. They are active in recycling the cell's organic material and in the intracellular digestion of macromolecules.Some cells, such as white blood cells, have many more lysosomes than others. These cells destroy bacteria, dead cells, cancerous cells, and foreign matter through cell digestion. Macrophages engulf matter by phagocytosis and enclose it within a vesicle called a phagosome. Lysosomes within the macrophage fuse with the phagosome releasing their enzymes and forming what is known as a phagolysosome. The internalized material is digested within the phagolysosome. Lysosomes are also necessary for the degradation of internal cell components such as organelles. In many organisms, lysosomes are also involved in programmed cell death.
No comments