Microtubules

Microtubules are made up of hollow tubes that make up a network to move organelles everywhere inside the eukaryotic cell.

They are made of thick microfilaments and consist of thousands of subunit spirals that are very strong and are aligned in 13 columns.

The subunits are made of the substance “tubulin” and this is why microtubules have their name.

They give the cell its rigidity, shape and organization. Microtubules have been given the nickname of the cell’s “railroad” because they act as a kind of conveyor belt for a lot of the structures that need to move around.

                                      Structure and assembly of microtubules

The job of Microtubules

Every eukaryotic cell will have a network of microtubules. Eukaryotic cells are those cells that have a nucleus.

The network system acts to move organelles all around the cell and it also helps to keep the organelles organized so that the cell is healthy.

Microtubules are considered to be part of the cell’s cytoskeleton and helps with the cell’s shape. They are the largest type of filaments that are found in a cell.

Another job that microtubules are responsible for is in helping to move the chromosomes when it’s time for the cell to divide.

In this job the mitotic spindles that are needed for cell division in both meiosis and mitosis are made of microtubules. They pull the cell apart by attaching centrioles to the chromosomes.

Microtubules: Creating the Tails for movement

Cells often have tails called “cilia” and “flagella” that help them move around and swim. These tails are made of long strands of microtubules.

The cilia and flagella act kind of like the propeller of a boat so that they can get from one point to another.

Microtubules Major Part in Mitosis

One of the ways that cells reproduce is through mitosis. This is the process of a cell dividing to create copies of itself.

There is a lot of preparation involved to get ready for mitosis and microtubules are a major player.

Centrioles are organelles that are made up of microtubules and after they are duplicated the centrioles move to opposite cell side.

Mitotic spindles which are thin microtubule filaments attach the centrioles to the chromosomes that are lined up and they pull apart the chromosomes so that they split apart to create two different cells.

Without the help of microtubules, cells would never be able to reproduce.

 Facts about Microtubules

  • The tubulins that make up microtubules can occur as single, double, triple, or even in bundles.
  • Instructions in the cell to create microtubules is started at the microtubule-organizing centers (also known as MTOCs)
  • While the tubular structure of an average microtubule is from 15-25 nm in diameter, scientists have listed them as “indefinite” in length. This means that there isn’t a minimum or maximum microtubule length.
  • If you look at microtubules under a high powered microscope, they kind of look like noodles.
  • Many of the cell parts have very specialized functions. The microtubule is one of the few parts that has quite a few different important functions.
  • Scientists believe that microtubules are involved in our own neuron receptors in our brains.

Interesting Facts about Biology

  • The classification of naming the various types of organisms on earth is constantly being changed, but the original and still used model was invented by a Swedish plant scientist by the name of Carolus Linnaeus.
  • A cell’s size isn’t configured by its length, but instead by its diameter.
  • An average cell in our bodies can be anywhere from 10-100 µm (µm stands for micron, which is 1 millionth of a meter or 1 thousandth of a millimeter).
  • The human body has over 200 different types of cells.
  • Our red blood cells can live up to 120 days.
  • Each day humans have between 50 and 70 billion cells that die.

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