The basic structure of cell consist of nucleus, plasma membrane and cytoplasm. Other than this different structures like Endoplasmic Reticulum(ER), Golgi body, Lysosomes, Mitochondria, Plastids and Vacuoles are also present. All of these are cell organelles. Presence of different cell organelles differ from organism to organism i.e. unicellular or multicellular organism. Cell organelle can be either membrane bound or can lack membrane.

Cell Organelles

Endoplasmic Reticulum(ER):

It is divided into Rough Endoplasmic Reticulum (RER) and Smooth Endoplasmic Reticulum (SER). Collectively, this cell organelle, appears as network of tubules and flattened sac like structures. Rough endoplasmic reticulum appears like flattened sac and has rough outer surface, as outer surface contains ribosomes on it. Ribosomes are sites for manufacture and transport of proteins. Smooth endoplasmic reticulum appears like tubules and manufacture lipids. They also remove harmful drugs and poisons from the cell . Proteins and lipids formed at endoplasmic reticulum is used in construction of plasma membranes. This process is known as membrane biogenesis. .

Golgi body / Golgi apparatus:

Golgi apparatus appears as flattened sac like structure arranged parallely one above the other called as cisterns. Cisterns are membrane bound vesicles that keeps material inside the apparatus separated from outside cytoplasm. This cell organelle package and process material i.e. proteins and lipids in and out of cell. Golgi apparatus converts simple sugars into complex sugar. It also forms lysosomes.

Lysosomes:

Lysosomes are membrane bound, spherical shaped structure filled with digestive enzymes that are manufactured by RER. This cell organelle, digest waste by breaking it into small pieces and keeps cell clean. If cell gets damaged it digests its own cell. Hence, lysosome is also known as suicide bags of cell.

Mitochondria:

It is made up of inner and outer membrane. Outer membrane separates internal part of mitochondria from other cell organelles, whereas, inner membrane has folded structures called cristae. Mitochondria contains fluid called matrix containing DNA of mitochondria, ribosomes, etc. This cell organelles is called as powerhouse of cell as it stores energy in the form of ATP i.e. Adenosine Triphosphate molecule. These are generated on the folds of inner membrane. Energy stored in this cell organelle is used during chemical activities or while performing mechanical work. Mitochondria can generate protein due to presence of ribosomes.

Plastids:

This cell organelle is present only in plant cell appears like mitochondria. Plastids are made of large number of layers fixed in a material called stroma. It contains its own DNA and ribosomes. Plastids are of two types chromoplast i.e. coloured plastid and leucoplast i.e. white plastid. Plastids manufacture and store food in plants. Chromoplast in the form of chloroplast is used in photosynthesis. Leucoplast stores materials like starch, oil and proteins granules, etc.

Vacuoles:

This cell organelle stores solid or liquid material. In plants vacuoles are large taking maximum part of plant cell , whereas, in animal cells vacuoles are small. In plants, vacuoles stores material like amino acid, sugar, proteins, etc. turgidity of cells is due to vacuoles. In unicellular organisms vacuoles removes excess of water and waste material out of cell. It also stores food items consumed by organisms.

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Keywords: Cell organelle, endoplasmic reticulum, rough endoplasmic reticulum, smooth endoplasmic reticulum, golgi complex, golgi body, golgi apparatus, lysosomes, mitochondria, powerhouse of cell, plastids, vacuoles, ATP, adenosine triphosphate