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Main Part of the human cell


-cell membrane

What it does?

Every cell is considered a membrane. The cell membrane is the part that protects from the water being uncontrolled. The membrane is made up of important proteins.


What it does?

The cytoskeleton helps to maintain cell shape. But the importance of the cytoskeleton is in cell motility. The movement inside of the cell organelles, as well as cell locomotion and muscle fiber contraction could not take place without the cytoskeleton. The cytoskeleton is an organized network of three primary protein filaments:

- microtubules
- actin filaments (microfilaments)
- intermediate fibers



What it does?

The main structure in the nucleus is the nucleolus. The nucleolus produces ribosomes, which move out of the nucleus and take positions on the rough endoplasmic reticulum where they are really important  in protein synthesis.


What it does?

Ribosomes are packets of RNA and protein that play a big role in both prokaryotic and eukaryotic cells. They are the site of protein synthesis. Each ribosome has two parts, a large subunit and a small subunit. Messenger RNA from the cell nucleus is moves along the ribosome where transfer RNA adds individual amino acid molecules to the lengthening protein chain.

-endoplasmic reticulum

What it does?

There are two kinds of endoplasmic reticulum’s, a smooth endoplasmip reticulum and a rough endoplasmic reticulum.

Smooth Endoplasmic Reticulum-Throughout the eukaryotic cell,  is a network of membrane-bound vesicles and tubules called the endoplasmic reticulum, (ER). The ER is a continuation of the outer nuclear membrane and its varied functions suggest the complexity of the eukaryotic cell.
The smooth endoplasmic reticulum is so named because it appears smooth by electron microscopy. Smooth ER plays different functions depending on the specific cell type including lipid and steroid hormone synthesis, breakdown of lipid-soluble toxins in liver cells, and control of calcium release in muscle cell contraction.

Rough Endoplasmic Reticulum: Rough endoplasmic reticulum appears “pebbled” by electron microscopy because of  the presence of numerous ribosomes on the surface. Proteins synthesized on these ribosomes collect in the endoplasmic reticulum for transport throughout the cell.

-golgi apparatus

What it does?

The Golgi apparatus is a membrane-bound structure with a single membrane. Its a stack of membrane-bound vesicles that are important in packaging macromolecules for transport everywhere else in the cell. The stack of larger vesicles is surrounded by numerous smaller vesicles containing those packaged macromolecules. The enzymatic or hormonal contents of lysosomes, peroxisomes and secretory vesicles are packaged in membrane-bound vesicles at the periphery of the Golgi apparatus.


What it does?

Mitochondria gives the energy a cell needs to move, divide, produce secretory products, contract – in short, they are the power centers of the cell. They are about the size of bacteria but may have different shapes depending on the cell type. Mitochondria are membrane-bound organelles, and like the nucleus have a double membrane. The outer membrane is smooth. But the inner membrane is highly convoluted, forming folds. The cristae increases a lot in the inner membrane’s surface area. It is on these cristae that food (sugar) is combined with oxygen to produce ATP – the primary energy source for the cell.

Posted by on November 18, 2010 at 5:37 pm

One Response to “What are the main parts of a human cell & what does each do?”
  1. 1
      mnn says:

    wow can u put all that in a smaller sentence for i can understand a Lil better =)