The human body is organised in a specialised order that builds us as human beings called the
organisation of the human body which includes the smallest part of the body known as the cells,
examples of cells are the blood cells, stem cells, bone cells, muscle cells, nerve cells, these cells carry
out various chemical reactions that keep us alive. Cells bind together to form groups this creates
tissues, such as muscle tissues, nervous tissue, and epithelial tissue. This then builds organs like the
lungs, liver; heart stomach. A collection of organs that work together are known as an organ system
such as respiratory system, nervous system, muscular system, digestive system, overall resulting in
the human body being formed due to all these components.
Every living thing is recognised as an organism, every organism consists of cells, these cells are made
up of material and instructions that help our tissues, organs and organ systems have specialised
functions that work within the body. The parts of the animal cell are explained below:
Cell membrane:
The cell membrane’s structure is a wall protecting the inside of the cell from its environment; this
wall is made up of proteins and fats. Its semi permeable wall meaning it can allow gases like oxygen
and carbon dioxide to pass through as well as preventing other substances to pass through that can
be harmful. Its prime purpose is to protect and support the components of the cell within its walls,
while at the same time maintaining its rounded shape.
Nucleus:
The nucleus lies in the centre of the animal cell and is the largest organelle of the cell; it is
surrounded by the nuclear membrane. Its function involves maintaining the genetic material
enclosed in its walls. It is the control centre for the cell, this enables the activities of the cell.
Cytoplasm:
The Cytoplasm is found in the plant and animal cell. The structure consists of a jelly like substance.
This is where chemical reactions take place. Its jelly like substance is made from water, salts and
proteins. There are also molecule enzymes in the cytoplasm their purpose is to break down and
dispose of waste. Its job role entitles it to be responsible for its shape and the maintenance of the
organelles in their positions. Without the cytoplasm the cell’s organelles wouldn’t be able to provide
for other organelles.
Ribosome:
Ribosomes structure involves it having a flattened globe shaped appearance. With a diameter
between 15 to 25nm. Ribosomes are made up of Rrna and proteins. It’s the main responsibility is to
carry out protein synthesis to does this by the DNA providing a Mrna strand, this instructs the
ribosome to collect amino acid to build proteins for the cell. Ribosomes normally float around the
cytoplasm and can be attached to other organelles, waiting for their duties of the Mrna.
Mitochondria:
Mitochondria’s structure is presented with two membranes. The outer membrane acts as a
protective skin which covers the whole organelle. The second layer is the inner membrane, within
this layer there are folds which are named cristae. There is also a fluid in the mitochondria named
the matrix. Many chemicals reactions occur within the inner membrane as there is a bigger surface
area. The mitochondria are labelled the “powerhouse” as its function within the inner membrane of
, the mitochondria is to release and preserve energy for cell respiration. This occurs due the chemical
reactions within the Matrix as it contains water, proteins which create enzymes.
Endoplasmic reticulum:
The endoplasmic reticulum (ER) structure consists of a network of membranes. There are two parts
of ER with two different structures and functions. Firstly, there is the rough ER this is presented as
flattened sacs. Along with the smooth ER which has folded tubes. Within the rough ER’s structure, it
has ribosomes attached to its membrane. This allows the ER to produce proteins, these then can be
delivered to the Golgi body. Secondly there is the smooth ER which is not covered with ribosomes.
This ER is responsible for making and delivering lipids to the Golgi body.
Golgi apparatus/body:
The Golgi apparatus’s structure is arranged in folded stacks, sacs and vesicles also have infolds called
cisternae. The Golgi apparatus’s function involves receiving proteins from the Endoplasmic reticulum
(ER). The Golgi body intakes these proteins and changes their shape in order to suit the Golgi
apparatus’s structure, while at the same time the proteins are receiving attachments to lipids and
carbohydrates. Once this is achieved they are ready to be delivered to the organs in the body.
Lysosome:
Lysosome is a single membrane organelle meaning its structure involves it having a single
membrane, it has sacs that are full of fluidly enzymes. The lysosomes are created in the rough
endoplasmic reticulum. So are therefore part of the process between the ER and Golgi body as they
are delivered to the Golgi body by the ER as the Golgi body needs lysosome vesicle enzymes to carry
out its particular function. When the lysosomes vesicles are not needed for the Golgi body may float
around in the cytoplasm. However, when they are needed, the lysosome carries out its function by
working to break down and digest food and nutrients. They are commonly labelled “suicide bags “as
after the cell has died it has the ability to destroy itself.
P2: Outline the structure of the main tissues of the body
Firstly, a group of similar cells make up tissues, this then enables the tissue to carry out its particular
function. Within the human body there are four types of tissue these include Epithelial, Connective,
Muscle and Nervous tissue.
Epithelial:
Epithelial tissue has a membrane that lines the internal and external body parts. Organised in sheets
of cells that are closely connected to each other. Responsible for transferring substances into and
out of the blood. Creates hormones, all the glands in the body are made up of this tissue. This is due
to its protective layer which protects the organs from injury and prevents the body from infections.
All the tissue types within the epithelial are in connect with the base membrane. (Lumen, 2018)
Within the epithelial, there are two main tissues types such as simple epithelial and compound
epithelial.
Simple epithelial:
Has one cell layer in which the cells are arranged, which is in direct contact with the base membrane.
Within the simple epithelial there are tissue types called cuboidal, Columnar, Squamous, Ciliated.
Cuboidal: