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Parts of a Human Cell

Updated on September 25, 2012
The nucleus is the most visible and largest part of the cell.
The nucleus is the most visible and largest part of the cell. | Source

Since humans are animals, their cells share the same structures and organelles as all animals. The basic structures in all of our cells are the same as those found in cats, fish and spiders.

Therefore, once you learn what's in an animal cell, you know what's in most of the animals around you!

You should note that the cell structure of a plant is quite different (though still sharing the most fundamental parts of a cell - nucleus, cell membrane etc.) from that of an animal.

1. Nucleus

Like (almost) all cells, the typical human cell will contain a nucleus. This contains the DNA (in the form of chromosomes) necessary for all metabolic procedures that go on in the cell.

The nucleus contains all the information (you can think of it as 'blueprints') for the production of everything that is made in that cell.

Depending on the cell, the DNA in the nucleus will make different things, for example in a muscle cell, lots of proteins will be made that will carry out the processes for our movement.

The nucleus is also in charge of making ribosomes for the cell.

Amino acids being processed through a ribosome to make proteins!
Amino acids being processed through a ribosome to make proteins! | Source

2. Ribosomes

Ribosomes are small circular organelles (think of them as mini organs that cells use to function) that are responsible for the production of all of our proteins.

The appropriate amino acids are chained together with the help of something known as mRNA (messenger ribonucleic acid) and tRNA (transport ribonucleic acid) to make long chains known as proteins.

Proteins are of course fundamental to our survival and allow us to perform the majority of functions within the body.

Ribosomes are held in place within the cell by the structures known as microtubules.

3. Microtubules

Extensive amounts of microtubules act as the skeleton of a human cell, giving it support and holding the organelles in place.

Composed of the protein tubulin (created in the ribosomes), the microtubules of a cell coordinate countless processes in the cell, some of which we are not even sure about to this day.

What a mitochondrion looks like. The infolding of its membrane give higher surface area for the processes or respiration to occur.
What a mitochondrion looks like. The infolding of its membrane give higher surface area for the processes or respiration to occur. | Source

4. Mitochondria

Mitochondria act as the powerhouse for the cell, it provides storable energy by producing ATP which can then be utilised for energy by hydrating (adding water to it) and making it lose its third phosphate.

Without the mitochondria, respiration could not occur in the cell and it would not be able to function at all.

5. Cell membrane

The cell membrane acts as the 'coat' for cells making up its outer layer. It allows some substances into the cell and some substances out of it and is therefore known to be 'semi-permeable'.

The cell membrane also gives it a a degree of support and together with the microtubules give a human cell its characteristic globular shape (though not all cells are this shape).

The cell membrane is made up of what is known as a phospholipid bilayer which makes it waterproof and also allows it to have channels in it that can allow bigger proteins and substances into the cell since without them only a very limited amount of small molecules could have entered.

6. Smooth and Rough Endoplasmic Reticulum

The Smooth Endoplasmic Reticulum (SER) is much like the Rough Endoplasmic Reticulum except it doesn't have any of its characteristic ribosomes attached to it.

Otherwise, both are just folds of cell membrane that act as a channel for new proteins, giving them room and time to fold correctly into their tertiary and quaternary stages (each protein starts off one shape and then changes into another via the endoplasmic reticulum).

The (RER) is also responsible for the production of proteins which are then channelled through its endoplasmic reticulum.

7. Golgi Apparatus

After a protein has been passed through the endoplasmic reticulum it reaches the Golgi apparatus which modifies the protein, adding signal proteins to it that allow the newly modified protein to go where it needs to around our body.

The Golgi apparatus is also responsible for packaging the newly produced protein into something known as a vesicle (which is simply a membrane capsule) for expulsion out of the cell via a process known as exocytosis.

This is merely the vesicle (membrane ball) fusing with the cell membrane and then letting the protein inside of it float outside.

A Video Summarising All That You've Learned


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    • Vandna Vandna profile image

      Vandna Vandna 2 years ago


    • Philanthropy2012 profile image

      DK 5 years ago from London

      Thank you very much! :)

    • annerivendell profile image

      annerivendell 5 years ago from Dublin, Ireland

      Interesting Hub, and well researched.