Cells are the building
blocks of all living things, large or small, plant, animal or human beings. Water makes up about two thirds of the weight
of cells. Cells are very small and can
only be seen through a microscopy. Human
being are composed of trillions of cells and each cells have their own
specialized functions. It is these cells
that provide structure for our body, use the nutrients from our food and carry
out important functions. Cells are
capable of reproducing themselves so each cells in your body was made from an
already existing cell. Cells group
together to form tissues in our body, which in turn group together to form
organ such as brain and heart and other organs.
Our cells contain function structures called organelles and the responsibilities
of these organelles is to carry out tasks such as making proteins, processing
chemicals and generating energy for the cell.
At the centre of the cell is nucleus and is the control room for the
cell. The genome is found within the
nucleus. A genome is an organism’s
complete set of DNA, including all of it’s gene. Each genome contains all of the information that
is needed to build and maintain that organism.
In humans, a copy of the entire genome or more than 3 billion DNA base
pairs is contained in all cells that have a nucleus.
All the cells have a
membrane. Cell membranes are the outer
layers that hold the cells together. The
let in nutrients pass into the cell and waste products pass out. Note that not everything can pass through a
cell membrane. What gets in and what doesn’t
get depends on both the size of the particle trying to get in and the size of
the opening in the membrane.
Cells also have a
nucleus. This is the cell’s control
center. Cells continually dived to make
more cells for growth and repair in your body.
The nucleus contains the information that allows cells to reproduce or
make more cells. An important part of
the cell is the mitochondrion. This is
the part of a cell where food and oxygen combine to make energy.
