Golgi Apparatus – Definition, Structure, Functions, FAQs
The cell is the basic structural and functional unit of living organisms. In biology, the cell has the same central position as that of an atom in the physical sciences. The bodies of living organisms are made up of microscopic units called cells. Cells have evolved a variety of different lifestyles. Many organisms, such as bacteria(both archaebacteria and eubacteria), protozoa(e.g., amoeba), and yeasts consist of single cells (called unicellular organisms) that have the ability to perform a function like self-replication. More complex organisms, called multicellular organisms, those consists of collections of cells that perform particular functions.
Term cell was discovered by Robert Hook in his book ‘Micrographia’. The size of the cell is 10-16 micrometers. The shape of the cell may be polygonal, disc-like amoeboid,thread-like, cuboid or irregular, oval, hexagonal, circular, branched, elongated, etc. The cells are too small to be seen with naked eyes. so, it is studied with the help of microscopes.
Cell organelles are “small organs” of the cell and are found embedded in the cytosol. They form a living part of the cell and each of them has a definite shape, structure, and function. Different cell organelles are present in a cell such as ER(endoplasmic reticulum), Ribosomes, Golgi apparatus, Lysosomes, etc.
Golgi Apparatus (Golgi Body or Golgi complex) is a complex cytoplasmic structure that is made up of smooth membrane saccules or cisternae, and a network of tubules with vesicles and vacuoles. Golgi Apparatus exists as an extensive network near the nucleus in animal cells. However, the plant cells contain many freely distributed subunits of Golgi Apparatus, called dictyosomes. cisternae are formed at one end of the stack, called the cis face of Golgi. They are budded off as vesicles at the other face of the Golgi apparatus, called the trans face of Golgi.
Golgi apparatus was first visualized by George but named after Camillo Golgi who recognized the Golgi complex in the nerve cells of owl and cat by means of the metallic impregnation method.
Occurrence: The Golgi body is not present in bacteria, blue-green algae, mature sperms, and red blood cells of mammals and other animals.
Location: Golgi complex or apparatus in animal cells is either single or consists of a single connected complex respectively called localized (most vertebrate cells) and diffused(most invertebrate cells, liver and nerve cells of vertebrates).
Structure: The shape and size of the Golgi complex depend upon the physiological state of the cells. Mainly it is composed of four parts – cisternae, tubules, vesicles, and vacuoles.
Functions of Golgi Apparatus
- Golgi complex help in membrane transformation and membrane recycling.
- Proteins synthesized by the rough endoplasmic reticulum reach the cisternae of the Golgi apparatus where they combine with carbohydrates to form glycoproteins.
- Golgi apparatus mediates the production of hormones by endocrine glands.
- It forms the matrix of connective tissue.
- It helps in the formation of root hair from their mother cells.
- In chick embryos, the retinal pigment is synthesized by the Golgi complex.
Frequently Asked Questions
Question 1: What do you mean by cell organelles?
Cell organelles are “small organs” of the cell and are found embedded in the cytosol.They form living part of the cell and each of them has a definite shape, structure and function.
Question 2: Who discovered the Golgi apparatus?
Camillo Golgi discovered the Golgi apparatus.
Question 3: Write the function of the Golgi apparatus.
Golgi complex help in membrane transformation and membrane recycling and it helps in the formation of root hair from their mother cells.
Question 4: What is the structure of the Golgi body?
The shape and size of Golgi complex depend upon the physiological state of the cells. Mainly it is composed of four parts – cisternae,tubules,vesicles and vacuoles.
Question 5: What would happen without a Golgi body?
Other cells and organs in the body would not function properly without the products that the Golgi body normally sends. In the absence of the Golgi apparatus, lysosomes would not be produced.
Please Login to comment...